Phenobarbital interactions

Phenobarbital (Luminal, Sezaby), a barbiturate has 442 documented interactions across the FDA labels and fact sheets we index: 240 major, 176 moderate, 23 minor, and 3 where a label reports no significant interaction. Each entry below quotes the sentence behind it. This drug page is a starting point, not a verdict for your situation.

Interactions from the label

Major interactions (240)

  • AbirateroneCYP2D6 inhibitorMajor

    CYP3A4 Inducers: Avoid concomitant strong CYP3A4 inducers during YONSA treatment. (Abiraterone label, Drug interactions)

  • • CYP3A Inducers: Avoid co-administration with strong CYP3A inducers. (Acalabrutinib label, Drug interactions)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • AlcoholAlcoholMajor

    Abuse and misuse of phenobarbital commonly involve concomitant use of other drugs, alcohol, and/or illicit substances, which is associated with an increased frequency of serious adverse outcomes [see Warnings and Precaution (5.3)]. (Phenobarbital label, Boxed warning)

  • Alfuzosinalpha blockerMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • CYP3A4 Inducers : Avoid coadministration of VIJOICE with a strong CYP3A4 inducer. (Alpelisib label, Drug interactions)

  • AlprazolambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • AmiodaroneantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Amitriptylinetricyclic antidepressantMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • AnagrelideQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • ApixabananticoagulantMajor

    • Simultaneous use of combined P-gp and strong CYP3A4 inducers reduces blood levels of apixaban: Avoid concomitant use. (Apixaban label, Drug interactions)

  • ApremilastPDE4 inhibitorMajor

    Drug Interactions : Use with strong cytochrome P450 enzyme inducers (e.g., rifampin, phenobarbital, carbamazepine, phenytoin) is not recommended because loss of efficacy may occur ( 5.5 , 7.1 ) (Apremilast label, Warnings and precautions)

  • AripiprazoleantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Arsenic trioxideQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • AsenapineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • AtazanavirantiretroviralMajor

    …(with or without ritonavir) with carbamazepine is contraindicated due to the risk for loss of virologic response and development of resistance [see Contraindications (4) ]. phenytoin, phenobarbital ↓ atazanavir ↓ phenytoin ↓ phenobarbital Coadministration of REYATAZ (with or without ritonavir) with phenytoin or phenobarbital is contraindicated due to the risk for… (Atazanavir label, Drug interactions)

  • Azelastine and fluticasoneantihistamineMajor

    • Avoid concurrent use of alcohol or other central nervous system (CNS) depressants with azelastine hydrochloride and fluticasone propionate nasal spray because further decreased alertness and impairment of CNS performance may occur. (Azelastine and fluticasone label, Warnings and precautions)

  • Azithromycinmacrolide antibioticMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Baclofenmuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Concomitant administration with oxcarbazepine or phenobarbital is not recommended. (Bictegravir, emtricitabine, and tenofovir alafenamide label, Drug interactions)

  • Strong CYP3A4 Inducers: Avoid concomitant use. (Bortezomib label, Drug interactions)

  • • Strong CYP3A Inducers: Avoid concomitant use with BOSULIF. (Bosutinib label, Drug interactions)

  • BrexpiprazoleantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • BuprenorphineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • BupropionantidepressantMajor

    Bupropion hydrochloride extended-release tablets (XL) are contraindicated in patients undergoing abrupt discontinuation of alcohol, benzodiazepines, barbiturates, and antiepileptic drugs [see Warnings and Precautions (5.3) and Drug Interactions (7.3)] . (Bupropion label, Contraindications)

  • SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) (Phenobarbital label, Contraindications)

  • SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) (Phenobarbital label, Contraindications)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) (Phenobarbital label, Contraindications)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • ButorphanolopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • CabotegravirantiretroviralMajor

    • Coadministration with carbamazepine, oxcarbazepine, phenobarbital, phenytoin, rifampin, and rifapentine. (Cabotegravir label, Contraindications)

  • Avoid chronic co-administration of strong CYP3A4 inducers (e.g., phenytoin, carbamazepine, rifampin, rifabutin, rifapentine, phenobarbital, St. (Cabozantinib label, Drug interactions)

  • Cannabidiol (prescription)anticonvulsantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CarbamazepineanticonvulsantMajor

    CNS Depressants The concomitant use of EQUETRO and other CNS depressants can increase the risk of respiratory depression, profound sedation, hypotension, and syncope. (Carbamazepine label, Drug interactions)

  • CarbinoxamineantihistamineMajor

    Avoid concurrent use of Carbinoxamine Maleate Extended-Release Oral Suspension with alcohol or other central nervous system depressants because additional impairment of central nervous system performance may occur. (Carbinoxamine label, Warnings and precautions)

  • CariprazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Carisoprodolmuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CetirizineantihistamineMajor

    Avoid concurrent use of QUZYTTIR with alcohol or other CNS depressants because additional reduction in alertness and additional impairment of CNS performance may occur. (Cetirizine label, Warnings and precautions)

  • ChlordiazepoxidebenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • ChloroquineantimalarialMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • ChlorpromazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Chlorzoxazonemuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CiprofloxacinfluoroquinoloneMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • CitalopramSSRIMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Clarithromycinmacrolide antibioticMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • ClobazambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • ClonazepambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Clonidinealpha-adrenergic agonistMajor

    Avoid use with other central nervous system (CNS) depressants ( 5.3 ) (Clonidine label, Warnings and precautions)

  • ClorazepatebenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • ClozapineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CodeineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Cyclobenzaprinemuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Dantrolenemuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Daridorexantsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • DarunavirantiretroviralMajor

    …elbasvir/grazoprevir Lipid modifying agents: lomitapide, lovastatin, simvastatin Opioid Antagonist: naloxegol PDE-5 inhibitor: sildenafil when used for treatment of pulmonary arterial hypertension Sedatives/hypnotics: orally administered midazolam, triazolam Co-administration of PREZISTA/ritonavir is contraindicated with drugs that are highly dependent on CYP3A for clearance… (Darunavir label, Contraindications)

  • Darunavir and cobicistatantiretroviralMajor

    Co-administration of PREZCOBIX or PREZCOBIX PED with CYP3A inducers may lead to lower exposures of darunavir and cobicistat and potential loss of efficacy of darunavir and possible resistance. (Darunavir and cobicistat label, Contraindications)

  • If concomitant administration of a strong CYP3A4 inducer cannot be avoided, consider a dose increase [see Dosage and Administration ( 2.3 )] . (Dasatinib label, Drug interactions)

  • DeflazacortcorticosteroidMajor

    Avoid use of moderate or strong CYP3A4 inducers with EMFLAZA, as they may reduce efficacy ( 7.1 ) (Deflazacort label, Drug interactions)

  • Desfluranegeneral anestheticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • DeutetrabenazineVMAT2 inhibitorMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Dextromethorphan and quinidineserotonergic drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • DiazepambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CONTRAINDICATIONS Diphenoxylate hydrochloride and atropine sulfate is contraindicated in: • Pediatric patients less than 6 years of age due to the risks of respiratory and central nervous system (CNS) depression (see WARNINGS ). (Diphenoxylate and atropine label, Contraindications)

  • DisopyramideantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Divalproex (valproate)anticonvulsantMajor

    Children under the age of two years are at a considerably increased risk of developing fatal hepatotoxicity, especially those on multiple anticonvulsants, those with congenital metabolic disorders, those with severe seizure disorders accompanied by mental retardation, and those with organic brain disease. (Divalproex (valproate) label, Boxed warning)

  • DofetilideantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • DoravirineantiretroviralMajor

    PIFELTRO is contraindicated when co-administered with drugs that are strong cytochrome P450 (CYP)3A enzyme inducers as significant decreases in doravirine plasma concentrations may occur, which may decrease the effectiveness of PIFELTRO [see Warnings and Precautions (5.2) , Drug Interactions (7.1) , and Clinical Pharmacology (12.3) ] . (Doravirine label, Contraindications)

  • • Avoid concomitant use of doxorubicin hydrochloride with inhibitors and inducers of CYP3A4, CYP2D6, and/or P-gp ( 7.1 ) (Doxorubicin label, Drug interactions)

  • Doxylamine and pyridoxineantihistamineMajor

    Central nervous system (CNS) depressants: Concurrent use with alcohol or other CNS depressants is not recommended ( 5.1 ) (Doxylamine and pyridoxine label, Warnings and precautions)

  • DronabinolcannabinoidMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • DronedaroneantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Droperidoldopamine antagonistMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Therefore, concomitant use with strong CYP3A inducers is not recommended [see Drug Interactions (7.1) and Clinical Pharmacology (12.3) ] . (Elexacaftor, tezacaftor, and ivacaftor label, Warnings and precautions)

  • EluxadolineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Alpha 1-adrenoreceptor antagonist: alfuzosin Anticonvulsants: carbamazepine, phenobarbital, phenytoin Antimycobacterial: rifampin Antipsychotics: lurasidone, pimozide Ergot Derivatives: dihydroergotamine, ergotamine, methylergonovine Herbal Products: St. (Elvitegravir, cobicistat, emtricitabine, and tenofovir label, Contraindications)

  • …virologic response and possible resistance to COMPLERA or to the class of NNRTIs [see Warnings and Precautions (5.7) , Drug Interactions (7) , and Clinical Pharmacology (12.3) ]: Anticonvulsants: carbamazepine, oxcarbazepine, phenobarbital, phenytoin Antimycobacterials: rifampin, rifapentine Glucocorticoid (systemic): dexamethasone (more than a single-dose)… (Emtricitabine, rilpivirine, and tenofovir label, Contraindications)

  • Erythromycinmacrolide antibioticMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • EscitalopramSSRIMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • EstazolambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Eszopiclonesedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Etomidategeneral anestheticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • EtravirineantiretroviralMajor

    Etravirine should not be used in combination with carbamazepine, phenobarbital, or phenytoin as co-administration may cause significant decreases in etravirine plasma concentrations and loss of therapeutic effect of Etravirine. (Etravirine label, Drug interactions)

  • FelbamateanticonvulsantMajor

    IT IS NOT KNOWN WHETHER CONCOMITANT USE OF OTHER ANTIEPILEPTIC DRUGS AND/OR OTHER DRUGS AFFECT THE INCIDENCE OF HEPATIC FAILURE. (Felbamate label, Boxed warning)

  • FentanylopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • FingolimodimmunosuppressantMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • FlecainideantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • FlibanserinCNS depressantMajor

    Preventing or Managing DI The concomitant use of ADDYI with CYP3A4 inducers is not recommended. (Flibanserin label, Drug interactions)

  • Fluconazoleazole antifungalMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • FlumazenilbenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • FluoxetineSSRIMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • FluphenazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • FosamprenavirantiretroviralMajor

    …Hypericum perforatum ) Lipid modifying agents: Lomitapide, lovastatin, simvastatin Non-nucleoside reverse transcriptase inhibitor: Delavirdine PDE5 inhibitor: Sildenafil (Revatio) (for treatment of pulmonary arterial hypertension) Sedative/hypnotics: Midazolam, triazolam Hypersensitivity to fosamprenavir calcium or amprenavir (e.g., Stevens-Johnson syndrome). (Fosamprenavir label, Contraindications)

  • GabapentinanticonvulsantMajor

    • Respiratory Depression: May occur with NEURONTIN when used with concomitant central nervous system (CNS) depressants, including opioids, or in the setting of underlying respiratory impairment. (Gabapentin label, Warnings and precautions)

  • GranisetronQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • HaloperidolantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • HydrocodoneopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • HydromorphoneopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • HydroxychloroquineQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • HydroxyzineantihistamineMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • IbutilideantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • IloperidoneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • • Strong CYP3A4 Inducers: Do not administer strong CYP3A4 inducers with CAMPTOSAR. (Irinotecan label, Drug interactions)

  • Isofluranegeneral anestheticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • IsoniazidantibioticMajor

    To avoid phenytoin intoxication, appropriate adjustment of the anticonvulsant should be made 5,6 . (Isoniazid label, Drug interactions)

  • Itraconazoleazole antifungalMajor

    Anticonvulsants Carbamazepine Not recommended 2 weeks before, during, and 2 weeks after TOLSURA treatment. (Itraconazole label, Drug interactions)

  • Avoid concomitant use of CYP3A4 inducers when using Corlanor. (Ivabradine label, Drug interactions)

  • KetamineCNS depressantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Ketoconazoleazole antifungalMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • LapatinibP-glycoprotein inhibitorMajor

    Avoid strong CYP3A4 inducers. (Lapatinib label, Drug interactions)

  • Strong CYP3A4 Inducers: Avoid coadministration of strong CYP3A4 inducers with VITRAKVI. (Larotrectinib label, Drug interactions)

  • Lemborexantsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • LenacapavirantiretroviralMajor

    Concomitant administration of SUNLENCA with oxcarbazepine or phenobarbital is not recommended. (Lenacapavir label, Drug interactions)

  • LevocetirizineantihistamineMajor

    Avoid concurrent use of alcohol or other central nervous system depressants with XYZAL. (Levocetirizine label, Warnings and precautions)

  • LevofloxacinfluoroquinoloneMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • LevorphanolopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • LoperamideQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Lopinavir and ritonavirantiretroviralMajor

    KALETRA once daily in combination with carbamazepine, phenobarbital, or phenytoin is not recommended. (Lopinavir and ritonavir label, Drug interactions)

  • LorazepambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • LorlatinibCYP3A4 inducerMajor

    Effect of Other Drugs on LORBRENA Strong CYP3A Inducers LORBRENA is contraindicated in patients taking strong CYP3A inducers [see Contraindication (4) ] . (Lorlatinib label, Drug interactions)

  • LoxapineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • LumateperoneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • LurasidoneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Strong CYP3A4 inducers (rifampin) reduce exposure to macitentan: avoid co-administration with OPSUMIT ( 7.1 , 12.3 ). (Macitentan label, Drug interactions)

  • MeperidineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Metaxalonemuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • MethadoneopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Methocarbamolmuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • MethohexitalbarbiturateMajor

    SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) (Phenobarbital label, Contraindications)

  • MidazolambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • MifepristoneCYP3A4 inhibitorMajor

    Avoid co-administration of mifepristone and CYP3A inducers such as rifampin, rifabutin, rifapentin, phenobarbital, phenytoin, carbamazepine, and St. (Mifepristone label, Drug interactions)

  • MorphineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • MoxifloxacinfluoroquinoloneMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • NalbuphineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Naldemedineopioid antagonistMajor

    John's Wort) Clinical Impact Significant decrease in plasma naldemedine concentrations, which may reduce efficacy [see Clinical Pharmacology (12.3) ] Intervention Avoid use of SYMPROIC with strong CYP3A inducers. (Naldemedine label, Drug interactions)

  • Nalmefeneopioid antagonistMajor

    Risk of Recurrent Respiratory and CNS Depression : A recurrence of respiratory depression is possible, therefore, keep the patient under continued surveillance and administer repeat doses of ZURNAI using a new auto-injector with each dose while awaiting emergency medical assistance. (Nalmefene label, Warnings and precautions)

  • Naloxegolopioid antagonistMajor

    Strong CYP3A4 inducers (e.g., rifampin) : Decreased concentrations of naloxegol; concomitant use is not recommended. (Naloxegol label, Drug interactions)

  • Naltrexone and bupropionopioid antagonistMajor

    CYP2B6 Inducers (e.g., ritonavir, lopinavir, efavirenz, carbamazepine, phenobarbital, and phenytoin) may reduce efficacy by reducing bupropion exposure, avoid concomitant use. (Naltrexone and bupropion label, Drug interactions)

  • Nifedipinedihydropyridine calcium channel blockerMajor

    John’s Wort reduce the bioavailability and efficacy of nifedipine; therefore nifedipine should not be used in combination with strong CYP3A inducers such as rifampin (See CONTRAINDICATIONS ). (Nifedipine label, Drug interactions)

  • NilotinibQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • …contraindicated with drugs that are primarily metabolized by CYP3A and for which elevated concentrations are associated with serious and/or life-threatening reactions and drugs that are strong CYP3A inducers where significantly reduced nirmatrelvir or ritonavir plasma concentrations may be associated with the potential for loss of virologic response and possible resistance. (Nirmatrelvir and ritonavir label, Contraindications)

  • Counsel patients to use a back-up method or alternative method of contraception when enzyme inducers are used with COCs ( 7.1 ) -- - ---------- ------ USE IN SPECIFIC POPULATIONS---- -- -- --------- ---- Lactation: Not recommended; Lo Loestrin Fe can decrease milk production ( 8.2 ) (Norethindrone and ethinyl estradiol label, Drug interactions)

  • OfloxacinfluoroquinoloneMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • OlanzapineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Olanzapine and fluoxetineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • OliceridineopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • OlopatadineantihistamineMajor

    • Avoid concurrent use of alcohol or other central nervous system depressants with olopatadine hydrochloride nasal solution (nasal spray) ( 5.2 ). (Olopatadine label, Warnings and precautions)

  • Olopatadine and mometasoneantihistamineMajor

    • Avoid concurrent use of alcohol or other central nervous system (CNS) depressants with RYALTRIS because additional reductions in alertness and additional impairment of CNS performance may occur. (Olopatadine and mometasone label, Warnings and precautions)

  • OndansetronQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Orphenadrinemuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • OxazepambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • OxycodoneopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • OxymorphoneopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • PalbociclibCYP3A4 inhibitorMajor

    • CYP3A Inducers: Avoid concurrent use of IBRANCE with strong CYP3A inducers. (Palbociclib label, Drug interactions)

  • PaliperidoneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • VOTRIENT is not recommended if chronic use of strong CYP3A4 inducers cannot be avoided. (Pazopanib label, Drug interactions)

  • PentamidineQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • PerphenazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • PhenelzineMAO inhibitorMajor

    Phenelzine sulfate should not be used in combination with dextromethorphan or with CNS depressants such as alcohol and certain narcotics. (Phenelzine label, Contraindications)

  • SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) (Phenobarbital label, Contraindications)

  • Physostigminecholinesterase inhibitorMajor

    …spasms in the urinary tract collection system, inactivation of nerve and muscle cells after administration of drugs to relax the muscles (depolarization block after depolarizing muscle relaxants), in case of intoxication due to “irreversibly acting” cholinesterase inhibitors (drugs used to treat dementia), intoxication with phosphoric acid esters or barbiturates. (Physostigmine label, Contraindications)

  • PimavanserinantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • PimozideantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • PitolisantQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Posaconazoleazole antifungalMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • • Patients taking strong Cytochrome P450 3A enzyme (CYP3A) inducers, such as rifampin, [see Warnings and Precautions ( 5.6 ) and Drug Interactions ( 7.1 , 7.2 )] . (Praziquantel label, Contraindications)

  • PregabalinanticonvulsantMajor

    • Respiratory Depression : May occur with LYRICA when used with concomitant CNS depressants or in the setting of underlying respiratory impairment. (Pregabalin label, Warnings and precautions)

  • PrimidoneanticonvulsantMajor

    SEZABY is contraindicated in patients with: acute porphyrias [see Warnings and Precautions (5.8)], or a history of hypersensitivity reaction to phenobarbital or other barbiturates [see Warnings and Precautions (5.7)] Acute porphyrias (4) (Phenobarbital label, Contraindications)

  • ProcainamideantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • ProchlorperazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • PromethazineantihistamineMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • PropofolCNS depressantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • QuetiapineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • QuinidineantiarrhythmicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • QuinineantimalarialMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Ramelteonsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • RanolazineQT-prolonging drugMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • RemifentanilopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • RilpivirineantiretroviralMajor

    Table 2: Drugs That are Contraindicated with EDURANT and EDURANT PED Drug Class Contraindicated Drugs in Class Clinical Comment Anticonvulsants Carbamazepine Oxcarbazepine Phenobarbital Phenytoin Potential for significant decreases in rilpivirine plasma concentrations due to CYP3A enzyme induction, which may result in loss of virologic response. (Rilpivirine label, Contraindications)

  • • Strong and Moderate CYP3A Inducers: Avoid concomitant administration. (Rimegepant label, Drug interactions)

  • RisperidoneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • RitlecitinibJAK inhibitorMajor

    • Certain CYP3A inducers: Coadministration with strong inducers of CYP3A is not recommended. (Ritlecitinib label, Drug interactions)

  • RitonavirantiretroviralMajor

    WARNING: DRUG-DRUG INTERACTIONS LEADING TO POTENTIALLY SERIOUS AND/OR LIFE THREATENING REACTIONS Co-administration of NORVIR with several classes of drugs including sedative hypnotics, antiarrhythmics, or ergot alkaloid preparations may result in potentially serious and/or life-threatening adverse events due to possible effects of NORVIR on the hepatic metabolism… (Ritonavir label, Boxed warning)

  • RivaroxabananticoagulantMajor

    Avoid concomitant use of XARELTO with drugs that are known combined P-gp and strong CYP3A inducers [see Drug Interactions (7.3) ] . (Rivaroxaban label, Warnings and precautions)

  • RoflumilastPDE4 inhibitorMajor

    Therefore the use of strong cytochrome P450 inducers (e.g., rifampicin, phenobarbital, carbamazepine, and phenytoin) with DALIRESP is not recommended [see Warnings and Precautions (5.4) and Clinical Pharmacology (12.3) ]. (Roflumilast label, Drug interactions)

  • RolapitantCYP2D6 inhibitorMajor

    Intervention: Avoid the use of VARUBI in patients who require chronic administration of strong CYP3A4 inducers. (Rolapitant label, Drug interactions)

  • • Avoid use with rifampin and strong CYP3A4 inducers ( 7.3 ). (Romidepsin label, Drug interactions)

  • Sevofluranegeneral anestheticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • SirolimusimmunosuppressantMajor

    Interaction with Strong Inhibitors and Inducers of CYP3A4 and/or P-gp Avoid concomitant use of sirolimus with strong inhibitors of CYP3A4 and/or P-gp (such as ketoconazole, voriconazole, itraconazole, erythromycin, telithromycin, or clarithromycin) or strong inducers of CYP3A4 and/or P-gp (such as rifampin or rifabutin) [ see Drug Interactions (7.2) ]. (Sirolimus label, Warnings and precautions)

  • Sodium oxybateCNS depressantMajor

    • Central Nervous System Depression Xyrem (sodium oxybate) is a CNS depressant. (Sodium oxybate label, Boxed warning)

  • Anticonvulsants: carbamazepine phenytoin phenobarbital ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended. (Sofosbuvir and velpatasvir label, Drug interactions)

  • SolifenacinanticholinergicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • • Strong CYP3A Inducers: Avoid strong CYP3A4 inducers. (Sorafenib label, Drug interactions)

  • Sotalolbeta blockerMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Suvorexantsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • TacrolimusimmunosuppressantMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Tamoxifenselective estrogen receptor modulatorMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • TapentadolopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • Tasimelteonsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • TemazepambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • TetrabenazineVMAT2 inhibitorMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • ThioridazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Avoid co-administration of strong CYP3A4 inhibitors (e.g., itraconazole, clarithromycin, ritonavir) and strong CYP3A4 inducers (e.g., rifampin, phenytoin) with TEPADINA due to the potential effects on efficacy and toxicity [see Clinical Pharmacology ( 12.3 ) ] . (Thiotepa label, Drug interactions)

  • ThiothixeneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Ticagrelorantiplatelet agentMajor

    • Avoid use with strong CYP3A inhibitors or CYP3A inducers. (Ticagrelor label, Drug interactions)

  • Tizanidinemuscle relaxantMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • TolterodineanticholinergicMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Avoid concomitant use of SAMSCA with strong CYP3A inducers. (Tolvaptan label, Drug interactions)

  • Toremifeneselective estrogen receptor modulatorMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • CYP3A inducers: Avoid concomitant strong CYP3A inducers ( 7.1 ) (Trabectedin label, Drug interactions)

  • TramadolopioidMajor

    WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS; DEPENDENCE AND WITHDRAWAL REACTIONS AFTER USE OF SEZABY FOR A LONGER DURATION THAN RECOMMENDED; and ABUSE, MISUSE AND ADDICTION WITH UNAPPROVED USE IN ADOLESCENTS AND ADULTS Risks from Concomitant Use with Opioids Concomitant use of phenobarbital products, including SEZABY, and opioids may result in profound sedation,… (Phenobarbital label, Boxed warning)

  • TrazodoneantidepressantMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • TretinoinretinoidMajor

    Avoid concomitant use with strong CYP3A inducers if possible. (Tretinoin label, Drug interactions)

  • TriazolambenzodiazepineMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • TrifluoperazineantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Strong CYP3A4 Inducers: Should be avoided as concomitant use will result in reduction of ubrogepant exposure. (Ubrogepant label, Drug interactions)

  • Ella should not be administered with CYP3A4 inducers [see Drug interactions (7.1) and Clinical Pharmacology (12.3) ] . (Ulipristal label, Warnings and precautions)

  • UpadacitinibimmunosuppressantMajor

    Strong CYP3A4 Inducers : Coadministration of RINVOQ/RINVOQ LQ with strong CYP3A4 inducers is not recommended. (Upadacitinib label, Drug interactions)

  • ValbenazineVMAT2 inhibitorMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Valproic acidanticonvulsantMajor

    Children under the age of two years are at a considerably increased risk of developing fatal hepatotoxicity, especially those on multiple anticonvulsants, those with congenital metabolic disorders, those with severe seizure disorders accompanied by mental retardation, and those with organic brain disease. (Valproic acid label, Boxed warning)

  • VardenafilPDE5 inhibitorMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • VenlafaxineSNRIMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Strong CYP3A Inducers : Avoid concomitant use with strong CYP3A inducers. (Vepdegestrant label, Drug interactions)

  • Voriconazoleazole antifungalMajor

    Drugs that Prolong the QT Interval : Avoid concomitant use. (Phenobarbital label, Drug interactions)

  • Zaleplonsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • ZiprasidoneantipsychoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

  • Zolpidemsedative-hypnoticMajor

    CNS depressants: Closely monitor for sedation and respiratory depression. (Phenobarbital label, Drug interactions)

Moderate interactions (176)

  • Acetazolamidecarbonic anhydrase inhibitorModerate

    By decreasing the gastrointestinal absorption of primidone, acetazolamide may decrease serum concentrations of primidone and its metabolites, with a consequent possible decrease in anticonvulsant effect. (Acetazolamide label, Drug interactions)

  • AlbendazoleModerate

    Risk of Neurologic Symptoms: Neurocysticercosis patients may experience cerebral hypertensive episodes, seizures or focal neurologic deficits after initiation of therapy; begin appropriate steroid and anticonvulsant therapy. (Albendazole label, Warnings and precautions)

  • Allopurinolxanthine oxidase inhibitorModerate

    Inform patients also that the central nervous system depressant effects of allopurinol tablets may be additive to those of alcohol and other CNS depressants. (Allopurinol label, Warnings and precautions)

  • AminophyllinemethylxanthineModerate

    30% increase Phenobarbital (PB) Similar to aminoglutethimide. (Aminophylline label, Drug interactions)

  • Amlodipinedihydropyridine calcium channel blockerModerate

    Blood pressure should be closely monitored when amlodipine is co-administered with CYP3A inducers. (Amlodipine label, Drug interactions)

  • Amlodipine and atorvastatindihydropyridine calcium channel blockerModerate

    Blood pressure should be closely monitored when amlodipine is co-administered with CYP3A inducers. (Amlodipine and atorvastatin label, Drug interactions)

  • Amlodipine and benazeprildihydropyridine calcium channel blockerModerate

    Blood pressure should be monitored when amlodipine is coadministered with CYP3A4 inducers (e.g. rifampicin, St. (Amlodipine and benazepril label, Drug interactions)

  • Amlodipine and olmesartandihydropyridine calcium channel blockerModerate

    Blood pressure should be closely monitored when amlodipine is co-administered with CYP3A inducers. (Amlodipine and olmesartan label, Drug interactions)

  • Amlodipine and valsartandihydropyridine calcium channel blockerModerate

    Blood pressure should be closely monitored when amlodipine is coadministered with CYP3A inducers (e.g. rifampicin, St. (Amlodipine and valsartan label, Drug interactions)

  • Amoxapinetricyclic antidepressantModerate

    Amoxapine may enhance the response to alcohol and the effects of barbiturates and other CNS depressants. (Amoxapine label, Drug interactions)

  • Articaine and epinephrinelocal anestheticModerate

    …cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicylic acid, sulfonamides Antimalarials chloroquine, primaquine Anticonvulsants phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine Monoamine Oxidase Inhibitors, Nonselective Beta-Adrenergic… (Articaine and epinephrine label, Drug interactions)

  • Aspirin and dipyridamoleantiplatelet agentModerate

    Anticonvulsants Salicylic acid can displace protein-bound phenytoin and valproic acid, leading to a decrease in the total concentration of phenytoin and an increase in serum valproic acid levels. (Aspirin and dipyridamole label, Drug interactions)

  • AxitinibModerate

    CYP3A4/5 Inducers Co-administration of rifampin, a strong inducer of CYP3A4/5, reduced the plasma exposure of axitinib in healthy volunteers. (Axitinib label, Drug interactions)

  • BeclomethasonecorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants and corticosteroids) should be monitored and treated with established standards of care. (Beclomethasone label, Warnings and precautions)

  • Alcohol, barbiturates or narcotics: Concomitant administration of thiazide diuretics with alcohol, barbiturates, or narcotics may potentiate orthostatic hypotension. (Benazepril and hydrochlorothiazide label, Drug interactions)

  • BexagliflozinSGLT2 inhibitorModerate

    Clinically Significant Interactions with Bexagliflozin Tablets UGT Enzyme Inducers Clinical Impact UGT Enzyme Inducers may significantly reduce exposure to bexagliflozin and lead to a decreased efficacy [ see Clinical Pharmacology ( 12.3 )]. (Bexagliflozin label, Drug interactions)

  • Inducers of CYP450 liver enzymes The simultaneous administration of bismuth subcitrate potassium, metronidazole and tetracycline hydrochloride and drugs that induce microsomal liver enzymes, such as phenytoin or phenobarbital, may accelerate the elimination of metronidazole, resulting in reduced plasma concentrations of metronidazole. (Bismuth subcitrate, metronidazole, and tetracycline label, Drug interactions)

  • Alcohol, barbiturates, or narcotics - potentiation of orthostatic hypotension may occur. (Bisoprolol and hydrochlorothiazide label, Precautions)

  • Brimonidinealpha-adrenergic agonistModerate

    Use with CNS depressants may result in an additive or potentiating effect. (Brimonidine label, Drug interactions)

  • Brimonidine and timololalpha-adrenergic agonistModerate

    Use with CNS depressants may result in an additive or potentiating effect. (Brimonidine and timolol label, Drug interactions)

  • Bromocriptinedopamine agonistModerate

    Therefore, potent inhibitors or inducers of CYP3A4 may increase or reduce the circulating levels of CYCLOSET, respectively. (Bromocriptine label, Drug interactions)

  • Central Nervous System (CNS) depressants Antihistamines have additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, antianxiety agents, etc.). Antihypertensive drugs Sympathomimetic may reduce the effects of antihypertensive drugs. (Brompheniramine, pseudoephedrine, and dextromethorphan label, Drug interactions)

  • BudesonidecorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, post menopausal status, tobacco use, advance age, poor nutrition, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants, oral corticosteroids) should be monitored and treated with established standards of care. (Budesonide label, Warnings and precautions)

  • Budesonide and formoterolcorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, postmenopausal status, tobacco use, advanced age, poor nutrition, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants, oral corticosteroids) should be monitored and treated with established standards of care. (Budesonide and formoterol label, Warnings and precautions)

  • Bupivacainelocal anestheticModerate

    Possible early warning signs of central nervous system (CNS) toxicity are restlessness, anxiety, incoherent speech, lightheadedness, numbness and tingling of the mouth and lips, metallic taste, tinnitus, dizziness, blurred vision, tremors, twitching, CNS depression, or drowsiness. (Bupivacaine label, Warnings and precautions)

  • Bupivacaine and epinephrinelocal anestheticModerate

    Possible early warning signs of central nervous system (CNS) toxicity are restlessness, anxiety, incoherent speech, lightheadedness, numbness and tingling of the mouth and lips, metallic taste, tinnitus, dizziness, blurred vision, tremors, twitching, CNS depression, or drowsiness. (Bupivacaine and epinephrine label, Warnings and precautions)

  • Buspironeserotonergic drugModerate

    Triazolam/flurazepam: Coadministration of buspirone with either triazolam or flurazepam did not appear to prolong or intensify the sedative effects of either benzodiazepine. (Buspirone label, Drug interactions)

  • Calcitriolvitamin D analogModerate

    Phenytoin/Phenobarbital The coadministration of phenytoin or phenobarbital will not affect plasma concentrations of calcitriol, but may reduce endogenous plasma levels of 25(OH)D 3 by accelerating metabolism. (Calcitriol label, Drug interactions)

  • CanagliflozinSGLT2 inhibitorModerate

    Examples: Rifampin, phenytoin, phenobarbital, ritonavir Insulin or Insulin Secretagogues Clinical Impact: The risk of hypoglycemia is increased when INVOKANA is used concomitantly with insulin secretagogues (e.g., sulfonylurea) or insulin. (Canagliflozin label, Drug interactions)

  • Candesartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Interactions with Hydrochlorothiazide Alcohol, barbiturates, or narcotics − Potentiation of orthostatic hypotension may occur. (Candesartan and hydrochlorothiazide label, Drug interactions)

  • CarmustineModerate

    Consider alternative drugs to phenobarbital. (Carmustine label, Drug interactions)

  • CaspofunginantifungalModerate

    Inducers of Hepatic CYP Enzymes Rifampin : Rifampin is a potent CYP3A4 inducer and concomitant administration with caspofungin acetate for injection is expected to reduce the plasma concentrations of caspofungin acetate for injection. (Caspofungin label, Drug interactions)

  • CenobamateanticonvulsantModerate

    Phenobarbital and Clobazam: Reduce dosage as needed when used concomitantly with XCOPRI. (Cenobamate label, Drug interactions)

  • Chloroprocainelocal anestheticModerate

    …procaine, ropivacaine, tetracaine Antineoplastic agents cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicylic acid, sulfonamides Antimalarials chloroquine, primaquine Anticonvulsants Phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine (Chloroprocaine label, Precautions)

  • Chlorothiazidethiazide diureticModerate

    Alcohol, Barbiturates, or Narcotics - potentiation of orthostatic hypotension may occur. (Chlorothiazide label, Drug interactions)

  • Cholestyraminebile acid sequestrantModerate

    Drug Interactions Cholestyramine for Oral Suspension USP may delay or reduce the absorption of concomitant oral medication such as phenylbutazone, warfarin, thiazide diuretics (acidic), or propranolol (basic), as well as tetracycline, penicillin G, phenobarbital, thyroid and thyroxine preparations, estrogens and progestins, and digitalis. (Cholestyramine label, Drug interactions)

  • CiclesonidecorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants and oral corticosteroids) should be monitored and treated with established standards of care. (Ciclesonide label, Warnings and precautions)

  • ClemastineantihistamineModerate

    Use with CNS Depressants Clemastine has additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, etc.). Use in Activities Requiring Mental Alertness Patients should be warned about engaging in activities requiring mental alertness such as driving a car or operating appliances, machinery, etc. (Clemastine label, Warnings)

  • ClindamycinantibioticModerate

    Inducers of CYP3A4 and CYP3A5 Inducers of CYP3A4 and/or CYP3A5 may reduce plasma concentrations of clindamycin. (Clindamycin label, Drug interactions)

  • Clomipraminetricyclic antidepressantModerate

    Administration of CMI has been reported to increase the plasma levels of phenobarbital, if given concomitantly ( see CLINICAL PHARMACOLOGY, Interactions ). (Clomipramine label, Drug interactions)

  • John's Wort (Hypericum perforatum) preparations, phenobarbital, carbamazepine, and rifampin, may reduce plasma concentrations of some estrogens, possibly resulting in a decrease in therapeutic effects and/or changes in the uterine bleeding profile. (Conjugated estrogens and bazedoxifene label, Drug interactions)

  • CyclosporineimmunosuppressantModerate

    John’s Wort rifampin oxcarbazepine octreotide phenobarbital orlistat phenytoin sulfinpyrazone terbinafine ticlopidine Bosentan Coadministration of bosentan (250 to 1000 mg every 12 hours based on tolerability) and cyclosporine (300 mg every 12 hours for 2 days then dosing to achieve a C min of 200 to 250 ng/mL) for 7 days in healthy subjects resulted in decreases… (Cyclosporine label, Drug interactions)

  • CyproheptadineantihistamineModerate

    CNS Depressants Antihistamines may have additive effects with alcohol and other CNS depressants, e.g., hypnotics, sedatives, tranquilizers, antianxiety agents. (Cyproheptadine label, Warnings)

  • Deferasiroxiron supplementModerate

    The concomitant use of Exjade with potent UGT inducers (e.g., rifampicin, phenytoin, phenobarbital, ritonavir) may result in a decrease in Exjade efficacy due to a possible decrease in deferasirox concentration. (Deferasirox label, Drug interactions)

  • Desogestrel and ethinyl estradioloral contraceptiveModerate

    Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate, rifabutin, rufinamide, aprepitant, and products containing St. (Desogestrel and ethinyl estradiol label, Drug interactions)

  • DexchlorpheniramineantihistamineModerate

    Use with CNS Depressants CORPHENA Oral Solution has additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, etc.). Use in Activities Requiring Mental Alertness Patients should be warned about engaging in activities requiring mental alertness such as driving a car or operating appliances, machinery, etc. (Dexchlorpheniramine label, Warnings)

  • Dexlansoprazoleproton pump inhibitorModerate

    Clinically Relevant Interactions Affecting DEXILANT When Coadministered with Other Drugs and Substances CYP2C19 or CYP3A4 Inducers Clinical Impact: Decreased exposure of dexlansoprazole when used concomitantly with strong inducers [see Clinical Pharmacology (12.3) ] . (Dexlansoprazole label, Drug interactions)

  • DiclofenacNSAIDModerate

    Exercise caution when prescribing ZIPSOR with concomitant drugs that are known to be potentially hepatotoxic (e.g., acetaminophen, antibiotics, antiepileptics). (Diclofenac label, Warnings and precautions)

  • Exercise caution when prescribing diclofenac sodium/misoprostol with concomitant drugs that are known to be potentially hepatotoxic (e.g., antibiotics, anti-epileptics). (Diclofenac and misoprostol label, Warnings and precautions)

  • MOTOFEN ® may potentiate the action of barbiturates, tranquilizers, narcotics, and alcohol. (Difenoxin and atropine label, Drug interactions)

  • DimenhydrinateantihistamineModerate

    The concomitant use of alcohol or other central nervous system depressants may have an additive effect. (Dimenhydrinate label, Warnings)

  • DiphenhydramineantihistamineModerate

    Drug Interactions Diphenhydramine hydrochloride has additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, etc). (Diphenhydramine label, Drug interactions)

  • Doxepintricyclic antidepressantModerate

    Potential additive effects when used in combination with CNS depressants or sedating antihistamines. (Doxepin label, Warnings and precautions)

  • Doxercalciferolvitamin D analogModerate

    Examples Glutethimide and phenobarbital Intervention If a patient initiates or discontinues therapy with an enzyme inducer, dose adjustment of doxercalciferol may be necessary. (Doxercalciferol label, Drug interactions)

  • Doxycyclinetetracycline antibioticModerate

    Barbiturates, carbamazepine and phenytoin decrease the half-life of doxycycline. (Doxycycline label, Drug interactions)

  • Drospirenone and ethinyl estradioloral contraceptiveModerate

    Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampin, topiramate and products containing St. (Drospirenone and ethinyl estradiol label, Drug interactions)

  • EfavirenzantiretroviralModerate

    Potential for Other Drugs to Affect Efavirenz Drugs that induce CYP3A activity (e.g., phenobarbital, rifampin, rifabutin) would be expected to increase the clearance of efavirenz resulting in lowered plasma concentrations [ see Dosage and Administration ( 2.2 ) ]. (Efavirenz label, Drug interactions)

  • Drugs that induce CYP3A activity (e.g., phenobarbital, rifampin, rifabutin) would be expected to increase the clearance of EFV resulting in lowered plasma concentrations. (Efavirenz, lamivudine, and tenofovir label, Drug interactions)

  • Emtricitabine and tenofovirantiretroviralModerate

    Other Agents Anticonvulsants: carbamazepine oxcarbazepine phenobarbital phenytoin ↓ TAF Consider alternative anticonvulsant. (Emtricitabine and tenofovir label, Drug interactions)

  • Hydrochlorothiazide When administered concurrently the following drugs may interact with thiazide diuretics: Alcohol, barbiturates, or narcotics Potentiation of orthostatic hypotension may occur. (Enalapril and hydrochlorothiazide label, Drug interactions)

  • ErlotinibModerate

    CYP3A4 Inducers Pre-treatment with a CYP3A4 inducer prior to erlotinib decreased erlotinib exposure [see Clinical Pharmacology (12.3) ]. (Erlotinib label, Drug interactions)

  • ErtapenemantibioticModerate

    If focal tremors, myoclonus, or seizures occur, patients should be evaluated neurologically, placed on anticonvulsant therapy if not already instituted, and the dosage of INVANZ re-examined to determine whether it should be decreased or discontinued. (Ertapenem label, Warnings and precautions)

  • EslicarbazepineanticonvulsantModerate

    Phenobarbital or Primidone: Higher dosage of APTIOM may be necessary. (Eslicarbazepine label, Drug interactions)

  • Esomeprazoleproton pump inhibitorModerate

    Table 4: Clinically Relevant Interactions Affecting Esomeprazole When Co-Administered with Other Drugs CYP2C19 or CYP3A4 Inducers Clinical Impact: Decreased exposure of esomeprazole when used concomitantly with strong inducers [see Clinical Pharmacology (12.3) ]. (Esomeprazole label, Drug interactions)

  • EstradiolestrogenModerate

    John's Wort preparations (Hypericum perforatum), phenobarbital, carbamazepine, and rifampin may reduce plasma concentrations of estrogens, possibly resulting in a decrease in therapeutic effects and/or changes in the uterine bleeding profile. (Estradiol label, Drug interactions)

  • Estradiol and dienogestoral contraceptiveModerate

    Women who take medications that are strong CYP3A4 inducers should not choose Natazia as their oral contraceptive while using these inducers and for at least 28 days after discontinuation of these inducers due to the possibility of increased breakthrough bleeding and/or decreased contraceptive efficacy. (Estradiol and dienogest label, Drug interactions)

  • John's wort ( Hypericum perforatum ) preparations, phenobarbital, carbamazepine, and rifampin may reduce plasma concentrations of estrogens, possibly resulting in a decrease in therapeutic effects and/or changes in the uterine bleeding profile. (Estradiol and norethindrone label, Drug interactions)

  • Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include: phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate, rifabutin, rufinamide, aprepitant, and products containing St. (Etonogestrel and ethinyl estradiol label, Drug interactions)

  • EverolimusimmunosuppressantModerate

    Strong CYP3A inducer and P-gp inducer : Increase the dosage as recommended. (Everolimus label, Drug interactions)

  • Exemestanearomatase inhibitorModerate

    Strong CYP 3A4 inducers: Concomitant use of strong CYP 3A4 inducers decreases exemestane exposure. (Exemestane label, Drug interactions)

  • Felodipinedihydropyridine calcium channel blockerModerate

    Anticonvulsants - In a pharmacokinetic study, maximum plasma concentrations of felodipine were considerably lower in epileptic patients on long-term anticonvulsant therapy (e.g., phenytoin, carbamazepine, or phenobarbital) than in healthy volunteers. (Felodipine label, Drug interactions)

  • FenoprofenNSAIDModerate

    Intervention: When phenobarbital is added to or withdrawn from treatment, dosage adjustment of FENOPROFEN CALCIUM may be required. (Fenoprofen label, Drug interactions)

  • FesoterodineanticholinergicModerate

    CYP3A4 Inducers No dosing adjustments are recommended in the presence of CYP3A4 inducers, such as rifampin and carbamazepine. (Fesoterodine label, Drug interactions)

  • FludrocortisonecorticosteroidModerate

    Barbiturates, phenytoin, or rifampin —increased metabolic clearance of fludrocortisone acetate because of the induction of hepatic enzymes. (Fludrocortisone label, Drug interactions)

  • FluticasonecorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, postmenopausal status, tobacco use, advanced age, poor nutrition, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants, oral corticosteroids), should be monitored and treated with established standards of care. (Fluticasone label, Warnings and precautions)

  • Fluticasone and salmeterolcorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants, oral corticosteroids) should be monitored and treated with established standards of care. (Fluticasone and salmeterol label, Warnings and precautions)

  • Folic acid (folate)Vitamin and mineralModerate

    These antiepileptic drugs lower folate levels, and folic acid supplements can in turn lower blood levels of the drug. (NIH Office of Dietary Supplements, Folate)

  • FosaprepitantCYP3A4 inhibitorModerate

    CYP3A4 Interactions: Fosaprepitant is a weak inhibitor of CYP3A4, and aprepitant, the active moiety, is a substrate, inhibitor, and inducer of CYP3A4; see Full Prescribing Information for recommendations regarding contraindications, risk of adverse reactions, and dosage adjustment of FOCINVEZ and concomitant drugs. (Fosaprepitant label, Warnings and precautions)

  • FosphenytoinanticonvulsantModerate

    John's wort may vary widely based on preparation. theophylline Drugs that may either increase or decrease phenytoin serum levels Antiepileptic drugs Phenobarbital, valproate sodium, valproic acid 7.2 Drugs Affected by Phenytoin or CEREBYX Table 7 includes commonly occurring drug interactions affected by phenytoin (the active metabolite of CEREBYX). (Fosphenytoin label, Drug interactions)

  • GefitinibModerate

    • CYP3A4 Inducer: Increase IRESSA to 500 mg daily in patients receiving a strong CYP3A4 inducer. (Gefitinib label, Drug interactions)

  • GlimepiridesulfonylureaModerate

    …including glimepiride, leading to worsening glycemic control: danazol, glucagon, somatropin, protease inhibitors, atypical antipsychotic medications (e.g., olanzapine and clozapine), barbiturates, diazoxide, laxatives, rifampin, thiazides and other diuretics, corticosteroids, phenothiazines, thyroid hormones, estrogens, oral contraceptives, phenytoin, nicotinic… (Glimepiride label, Drug interactions)

  • GlycopyrrolateanticholinergicModerate

    Other Anticholinergic Drugs There is potential for an additive interaction between glycopyrrolate and concomitantly used anticholinergic drugs (e.g., tricyclic antidepressants, anti-epileptics, class I antiarrhythmics, anti­-spasmodics, amantadine) resulting in increased anticholinergic adverse reactions. (Glycopyrrolate label, Drug interactions)

  • GriseofulvinantifungalModerate

    Barbiturates usually depress griseofulvin activity by decreasing plasma levels and concomitant administration may require a dosage adjustment of the antifungal agent. (Griseofulvin label, Drug interactions)

  • Guanfacinealpha-adrenergic agonistModerate

    Consider the potential for additive sedative effects with CNS depressant drugs. (Guanfacine label, Warnings and precautions)

  • HydrocortisonecorticosteroidModerate

    Concomitant administration of inducers of CYP3A4 may lead to decreases in serum concentrations of ALKINDI SPRINKLE and increase the risk of adverse reactions, including adrenal crisis. (Hydrocortisone label, Drug interactions)

  • IfosfamideModerate

    • CYP3A4 Inducers: Monitor for increased toxicity when used in combination with CYP3A4 inducers. (Ifosfamide label, Drug interactions)

  • ImatinibCYP3A4 inhibitorModerate

    CYP3A4 inducers may decrease Gleevec C max and area under curve (AUC). (Imatinib label, Drug interactions)

  • Imipenem and cilastatinantibioticModerate

    If focal tremors, myoclonus, or seizures occur, patients should be evaluated neurologically, placed on anticonvulsant therapy if not already instituted, and the dosage of PRIMAXIN re-examined to determine whether it should be decreased, or the antibacterial drug discontinued ( 5.2 ). (Imipenem and cilastatin label, Warnings and precautions)

  • Imipraminetricyclic antidepressantModerate

    Imipramine hydrochloride may enhance the CNS depressant effects of alcohol. (Imipramine label, Warnings)

  • IvacaftorCYP3A4 inhibitorModerate

    Concomitant Use with CYP3A Inducers Use of KALYDECO with strong CYP3A inducers, such as rifampin, substantially decreases the exposure of ivacaftor, which may reduce the therapeutic effectiveness of KALYDECO. (Ivacaftor label, Warnings and precautions)

  • LacosamideanticonvulsantModerate

    Anyone considering prescribing VIMPAT or any other AED must balance this risk with the risk of untreated illness. (Lacosamide label, Warnings and precautions)

  • LamotrigineanticonvulsantModerate

    Carbamazepine, phenytoin, phenobarbital, primidone, and rifampin decrease lamotrigine concentrations by approximately 40%. (Lamotrigine label, Drug interactions)

  • Lansoprazoleproton pump inhibitorModerate

    Clinically Relevant Interactions Affecting PREVACID or PREVACID SoluTab When Coadministered with Other Drugs CYP2C19 OR CYP3A4 Inducers Clinical Impact: Decreased exposure of lansoprazole when used concomitantly with strong inducers [see Clinical Pharmacology (12.3) ] . (Lansoprazole label, Drug interactions)

  • Ledipasvir and sofosbuvirantiviralModerate

    Anticonvulsants: carbamazepine phenytoin phenobarbital ↓ ledipasvir ↓ sofosbuvir Coadministration of ledipasvir and sofosbuvir with carbamazepine, phenytoin, or phenobarbital is expected to decrease the concentration of ledipasvir and sofosbuvir, leading to reduced therapeutic effect of ledipasvir and sofosbuvir. (Ledipasvir and sofosbuvir label, Drug interactions)

  • LeucovorinModerate

    Effects of VYKOURA on Other Drugs Certain Antiepileptic Drugs Increase monitoring for seizure activity in patients taking certain concomitant antiepileptic drugs. (Leucovorin label, Drug interactions)

  • Effects of Leucovorin Products on Other Drugs Antiepileptic Drugs Folic acid in large amounts may counteract the antiepileptic effect of phenobarbital, phenytoin and primidone and increase the frequency of seizures in susceptible children. (Levoleucovorin label, Drug interactions)

  • Levonorgestrel and ethinyl estradioloral contraceptiveModerate

    Enzyme inducers (e.g., CYP3A4) : May decrease the effectiveness of TYBLUME or increase breakthrough bleeding. (Levonorgestrel and ethinyl estradiol label, Drug interactions)

  • Levothyroxinethyroid hormoneModerate

    Drug or Drug Class Effect Phenobarbital Rifampin Phenobarbital has been shown to reduce the response to thyroxine. (Levothyroxine label, Drug interactions)

  • Lidocaine and epinephrinelocal anestheticModerate

    Possible early warning signs of central nervous system (CNS) toxicity are restlessness, anxiety, incoherent speech, lightheadedness, metallic taste, tinnitus, dizziness, blurred vision, tremors, twitching, CNS depression, or drowsiness. (Lidocaine and epinephrine label, Warnings and precautions)

  • Lidocaine and prilocainelocal anestheticModerate

    …prilocaine, procaine, ropivacaine, tetracaine Antineoplastic agents cyclophosphamide, flutamide, hydroxyurea, isofamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicylic acid, sufonamides Antimalarials chloroquine, primaquine Anticonvulsants Phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine (Lidocaine and prilocaine label, Drug interactions)

  • LinagliptinDPP-4 inhibitorModerate

    Strong P-glycoprotein/CYP3A4 inducer: The efficacy of TRADJENTA may be reduced when administered in combination (e.g., with rifampin). (Linagliptin label, Drug interactions)

  • Linagliptin and metforminDPP-4 inhibitorModerate

    Inducers of P-glycoprotein or CYP3A4 Enzymes Clinical Impact Rifampin decreased linagliptin exposure, suggesting that the efficacy of linagliptin may be reduced when administered in combination with a strong P-gp or CYP3A4 inducer. (Linagliptin and metformin label, Drug interactions)

  • Liothyroninethyroid hormoneModerate

    Drug or Drug Class Effect Phenobarbital Rifampin Phenobarbital has been shown to reduce the response to thyroxine. (Liothyronine label, Drug interactions)

  • Alcohol, barbiturates, or narcotics - potentiation of orthostatic hypotension may occur. (Lisinopril and hydrochlorothiazide label, Drug interactions)

  • Lofexidinealpha-adrenergic agonistModerate

    Increased Risk of CNS Depression with Concomitant use of CNS Depressant Drugs : Lofexidine tablets potentiates the CNS depressant effects of benzodiazepines and may potentiate the CNS depressant effects of alcohol, barbiturates, and other sedating drugs. (Lofexidine label, Warnings and precautions)

  • MaravirocantiretroviralModerate

    • If patients with severe renal impairment or ESRD receiving SELZENTRY (without concomitant CYP3A inducers or inhibitors) experience postural hypotension, the dose of SELZENTRY should be reduced from 300 mg twice daily to 150 mg twice daily. (Maraviroc label, Warnings and precautions)

  • MeclizineantihistamineModerate

    • Coadministration of meclizine hydrochloride with other CNS depressants, including alcohol, may result in increased CNS depression ( 7.1 ). (Meclizine label, Drug interactions)

  • MedroxyprogesteroneprogestinModerate

    MPA Injectable Suspension, USP can pose an additional risk in patients with risk factors for osteoporosis (e.g., metabolic bone disease, chronic alcohol and/or tobacco use, anorexia nervosa, strong family history of osteoporosis or chronic use of drugs that can reduce bone mass such as anticonvulsants or corticosteroids). (Medroxyprogesterone label, Warnings and precautions)

  • MefloquineantimalarialModerate

    Anticonvulsants In patients taking an anticonvulsant (e.g., valproic acid, carbamazepine, phenobarbital or phenytoin), the concomitant use of mefloquine may reduce seizure control by lowering the plasma levels of the anticonvulsant. (Mefloquine label, Drug interactions)

  • Memantine and donepezilcholinesterase inhibitorModerate

    Inducers of CYP3A4 (e.g., phenytoin, carbamazepine, dexamethasone, rifampin, and phenobarbital) could increase the rate of elimination of donepezil. (Memantine and donepezil label, Drug interactions)

  • Mepivacainelocal anestheticModerate

    …procaine, ropivacaine, tetracaine Antineoplastic agents cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicylic acid, sulfonamides Antimalarials chloroquine, primaquine Anticonvulsants phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine (Mepivacaine label, Drug interactions)

  • MeprobamateCNS depressantModerate

    Additive Effects Since the effects of meprobamate and alcohol or meprobamate and other CNS depressants or psychotropic drugs may be additive,appropriate caution should be exercised with patients who take more than one of these agents simultaneously. (Meprobamate label, Warnings)

  • MethsuximideanticonvulsantModerate

    Drug Interactions Since Celontin (methsuximide) may interact with concurrently administered antiepileptic drugs, periodic serum level determinations of these drugs may be necessary (eg, methsuximide may increase the plasma concentrations of phenytoin and phenobarbital). (Methsuximide label, Drug interactions)

  • Methylergonovineergot alkaloidModerate

    CYP3A4 inducers Drugs (e.g. nevirapine, rifampin) that are strong inducers of CYP3A4 are likely to decrease the pharmacological action of methylergonovine maleate. (Methylergonovine label, Drug interactions)

  • MethylprednisolonecorticosteroidModerate

    Hepatic Enzyme Inducers (e.g., barbiturates, phenytoin, carbamazepine, rifampin) : Drugs which induce cytochrome P450 3A4 enzyme activity may enhance the metabolism of corticosteroids and require that the dosage of the corticosteroid be increased. (Methylprednisolone label, Drug interactions)

  • Metoclopramidedopamine antagonistModerate

    Concomitant use of central nervous system (CNS) depressants or drugs associated with EPS may increase this effect (e.g., alcohol, sedatives, hypnotics, opiates, and anxiolytics). (Metoclopramide label, Warnings and precautions)

  • Metolazonethiazide diureticModerate

    Alcohol, Barbiturates, And Narcotics The hypotensive effects of these drugs may be potentiated by the volume contraction that may be associated with metolazone therapy. (Metolazone label, Drug interactions)

  • MetronidazoleantibioticModerate

    Inducers of CYP450 Liver Enzymes The simultaneous administration of LIKMEZ and drugs that induce microsomal liver enzymes, such as phenytoin or phenobarbital, may accelerate the elimination of metronidazole, resulting in reduced plasma concentrations of metronidazole. (Metronidazole label, Drug interactions)

  • MetyrosineModerate

    Concurrent use of metyrosine with alcohol or other CNS depressants can increase their sedative effects. (Metyrosine label, Drug interactions)

  • MirtazapineantidepressantModerate

    John's Wort, tramadol, tryptophan, buspirone Strong CYP3A Inducers Clinical Impact The concomitant use of strong CYP3A inducers with REMERON/REMERONSolTab decreases the plasma concentration of mirtazapine [see Clinical Pharmacology (12.3) ] . (Mirtazapine label, Drug interactions)

  • MometasonecorticosteroidModerate

    Patients with major risk factors for decreased bone mineral content, such as prolonged immobilization, family history of osteoporosis, or chronic use of drugs that can reduce bone mass (e.g., anticonvulsants and corticosteroids) should be monitored and treated with established standards of care. (Mometasone label, Warnings and precautions)

  • Naloxoneopioid antagonistModerate

    WARNINGS AND PRECAUTIONS Risk of Recurrent Respiratory and CNS Depression : Due to the duration of action of naloxone relative to the opioid, respiratory and CNS depression may recur after the first dose of naloxone. (Naloxone label, Warnings and precautions)

  • Table 4: Clinically Significant Interactions with Esomeprazole Magnesium - Affecting Co-Administered Drugs CYP2C19 or CYP3A4 Inducers Clinical Impact : Decreased exposure of esomeprazole when used concomitantly with strong inducers [see Clinical Pharmacology (12.3) ]. (Naproxen and esomeprazole label, Drug interactions)

  • NevirapineantiretroviralModerate

    Anticonvulsants: Carbamazepine, clonazepam, ethosuximide Plasma concentrations of nevirapine and the anticonvulsant may be decreased. (Nevirapine label, Drug interactions)

  • Nimodipinedihydropyridine calcium channel blockerModerate

    Possible Reduced Efficacy with Strong CYP3A4 Inducers Concomitant use of strong CYP3A4 inducers (e.g., carbamazepine, phenobarbital, phenytoin, rifampin, St. (Nimodipine label, Warnings and precautions)

  • NintedanibModerate

    Coadministration with oral doses of a P-gp and CYP3A4 inducer, rifampicin, decreased exposure to nintedanib by 50%. (Nintedanib label, Drug interactions)

  • Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate, rifabutin, rufinamide, aprepitant, and products containing St. (Norelgestromin and ethinyl estradiol label, Drug interactions)

  • NorethindroneprogestinModerate

    Some drugs or herbal products that may decrease the effectiveness of HCs include efavirenz, phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, rifabutin, rufinamide, aprepitant, and products containing St. (Norethindrone label, Drug interactions)

  • Norgestimate and ethinyl estradioloral contraceptiveModerate

    Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate, rifabutin, rufinamide, aprepitant, and products containing St. (Norgestimate and ethinyl estradiol label, Drug interactions)

  • Norgestrel and ethinyl estradioloral contraceptiveModerate

    Some drugs or herbal products that may decrease the effectiveness of hormonal contraceptives include phenytoin, barbiturates, carbamazepine, bosentan, felbamate, griseofulvin, oxcarbazepine, rifampicin, topiramate rifabutin, rufinamide, aprepitant, and products containing St. (Norgestrel and ethinyl estradiol label, Drug interactions)

  • Olmesartan, amlodipine, and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    Blood pressure should be closely monitored when amlodipine is co-administered with CYP3A inducers. (Olmesartan, amlodipine, and hydrochlorothiazide label, Drug interactions)

  • Omeprazoleproton pump inhibitorModerate

    Table 4: Clinically Relevant Interactions Affecting Omeprazole When Co-Administered with Other Drugs CYP2C19 or CYP3A4 Inducers Clinical Impact: Decreased exposure of omeprazole when used concomitantly with strong inducers [see Clinical Pharmacology ( 12.3 )] . (Omeprazole label, Drug interactions)

  • Omeprazole and sodium bicarbonateproton pump inhibitorModerate

    Table 6: Clinically Relevant Interactions Affecting Omeprazole when Co-Administered with Other Drugs CYP2C19 or CYP3A4 Inducers Clinical Impact: Decreased exposure of omeprazole when used concomitantly with strong inducers [see Clinical Pharmacology ( 12.3 )] . (Omeprazole and sodium bicarbonate label, Drug interactions)

  • OrlistatModerate

    Drug Interactions and Decreased Vitamin Absorption ORLISTAT may interact with concomitant drugs including cyclosporine, levothyroxine, warfarin, amiodarone, antiepileptic drugs, and antiretroviral drugs [see Drug Interactions (7) ]. (Orlistat label, Warnings and precautions)

  • OxcarbazepineanticonvulsantModerate

    Carbamazepine, Phenytoin, and Phenobarbital: Decreased plasma levels of MHD (the active metabolite). (Oxcarbazepine label, Drug interactions)

  • PerampanelanticonvulsantModerate

    Patients should be carefully observed for signs of central nervous system (CNS) depression, such as somnolence and sedation, when FYCOMPA is used with other drugs with sedative properties because of potential additive effects. (Perampanel label, Warnings and precautions)

  • Phentermine and topiramateCNS stimulantModerate

    The concomitant use of alcohol or central nervous system (CNS) depressant drugs with phentermine and topiramate extended-release capsules may potentiate CNS depression or other centrally mediated effects of these agents, such as dizziness, cognitive adverse reactions, drowsiness, light-headedness, impaired coordination, and somnolence. (Phentermine and topiramate label, Warnings and precautions)

  • PhenytoinanticonvulsantModerate

    Additionally, consider alternatives to structurally similar drugs such as carboxamides (e.g., carbamazepine) and hydantoins (e.g., phenytoin) in these same patients. (Phenobarbital label, Warnings and precautions)

  • Pioglitazone and glimepiridethiazolidinedioneModerate

    …including glimepiride, leading to worsening glycemic control: danazol, glucagon, somatropin, protease inhibitors, atypical antipsychotic medications (e.g., olanzapine and clozapine), barbiturates, diazoxide, laxatives, rifampin, thiazides and other diuretics, corticosteroids, phenothiazines, thyroid hormones, estrogens, oral contraceptives, phenytoin, nicotinic… (Pioglitazone and glimepiride label, Drug interactions)

  • PrednisolonecorticosteroidModerate

    CYP 3A4 inducers (e.g. barbiturates, phenytoin, carbamazepine, and rifampin): Drugs such as barbiturates, phenytoin, ephedrine, and rifampin, which induce hepatic microsomal drug metabolizing enzyme activity may enhance metabolism of prednisolone and require that the dosage of Orapred be increased. (Prednisolone label, Drug interactions)

  • PrednisonecorticosteroidModerate

    CYP 3A4 inducers and inhibitors: May, respectively, increase or decrease clearance of corticosteroids, necessitating dose adjustment. (Prednisone label, Drug interactions)

  • Prilocaine and epinephrinelocal anestheticModerate

    …cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicylic acid, sulfonamides Antimalarials chloroquine, primaquine Anticonvulsants phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine The administration of local anesthetic injections containing… (Prilocaine and epinephrine label, Drug interactions)

  • Protriptylinetricyclic antidepressantModerate

    Protriptyline may enhance the response to alcohol and the effects of barbiturates and other CNS depressants. (Protriptyline label, Drug interactions)

  • RepaglinidemeglitinideModerate

    CYP2C8 and CYP3A4 Inducers Intervention: Repaglinide tablets dose increases and increased frequency of glucose monitoring may be required when co‑administered. (Repaglinide label, Drug interactions)

  • RifabutinantibioticModerate

    Drug Interactions Effect of Rifabutin on the Pharmacokinetics of Other Drugs Rifabutin induces CYP3A enzymes and therefore may reduce the plasma concentrations of drugs metabolized by those enzymes. (Rifabutin label, Drug interactions)

  • RifampinantibioticModerate

    …Hormonal Contraceptives Prevention or Management: Advise patients to change to non-hormonal methods of birth control during rifampin therapy Estrogens Decrease exposure Progestins Anticonvulsants Phenytoin Administered with rifampin 450 mg daily Decrease exposure Antiarrhythmics Disopyramide Decrease exposure Mexiletine Decrease exposure Quinidine Decrease exposure… (Rifampin label, Drug interactions)

  • RifapentineantibioticModerate

    …Disopyramide, mexiletine, quinidine, tocainide Antibiotics Chloramphenicol, clarithromycin, dapsone, doxycycline; Fluoroquinolones (such as ciprofloxacin) Oral Anticoagulants Warfarin Anticonvulsants Phenytoin Antimalarials Quinine Azole Antifungals Fluconazole, itraconazole, ketoconazole Antipsychotics Haloperidol Barbiturates Phenobarbital Benzodiazepines Diazepam… (Rifapentine label, Drug interactions)

  • Rocuroniumneuromuscular blockerModerate

    Reduced Rocuronium Bromide Injection activity possible : Anticonvulsants. (Rocuronium label, Drug interactions)

  • Ropivacainelocal anestheticModerate

    …cyclophosphamide, flutamide, hydroxyurea, ifosfamide, rasburicase Antibiotics dapsone, nitrofurantoin, para-aminosalicylic acid, sulfonamides Antimalarials chloroquine, primaquine Anticonvulsants Phenobarbital, phenytoin, sodium valproate Other drugs acetaminophen, metoclopramide, quinine, sulfasalazine NAROPIN should be used with caution in patients receiving… (Ropivacaine label, Drug interactions)

  • RufinamideanticonvulsantModerate

    Table 6: Summary of drug-drug interactions of BANZEL with other antiepileptic drugs AED Co-administered Influence of Rufinamide on AED concentration a) Influence of AED on Rufinamide concentration Carbamazepine Decrease by 7 to 13% b) Decrease by 19 to 26% Dependent on dose of carbamazepine Lamotrigine Decrease by 7 to 13% b) No Effect Phenobarbital Increase… (Rufinamide label, Drug interactions)

  • RuxolitinibJAK inhibitorModerate

    Strong CYP3A4 Inducers Concomitant use of JAKAFI/JAKAFI XR with strong CYP3A4 inducers may decrease ruxolitinib exposure [ see Clinical Pharmacology ( 12.3 )] , which may reduce efficacy of JAKAFI/JAKAFI XR. (Ruxolitinib label, Drug interactions)

  • SapropterinModerate

    Inhibitors of Folate Synthesis (e.g., methotrexate, valproic acid, phenobarbital, trimethoprim) Clinical Impact In vitro and in vivo nonclinical data suggest that drugs that inhibit folate synthesis may decrease the bioavailability of endogenous BH4 by inhibiting the enzyme dihydrofolate reductase, which is involved in the recycling (regeneration) of BH4. (Sapropterin label, Drug interactions)

  • ScopolamineanticholinergicModerate

    Weigh this potential risk against the benefits before prescribing TRANSDERM SCŌP to patients with a history of seizures, including those receiving anti-epileptic medication or who have risk factors that can lower the seizure threshold. (Scopolamine label, Warnings and precautions)

  • SelegilineMAO inhibitorModerate

    Drugs that induce CYP3A4 (e.g., phenytoin, carbamazepine, nafcillin, phenobarbital, and rifampin) should be used with caution. (Selegiline label, Drug interactions)

  • Spironolactone and hydrochlorothiazidealdosterone antagonistModerate

    Alcohol, barbiturates, or narcotics: Potentiation of orthostatic hypotension may occur. (Spironolactone and hydrochlorothiazide label, Drug interactions)

  • SunitinibModerate

    • CYP3A4 Inducers : Consider dose increase of SUTENT when administered with strong CYP3A4 inducers. (Sunitinib label, Drug interactions)

  • TadalafilPDE5 inhibitorModerate

    CYP3A4 inhibitors (e.g. ketoconazole, ritonavir) increase CIALIS exposure ( 2.7 , 5.10 , 7.2 ) requiring dose adjustment: CIALIS for use as needed: no more than 10 mg every 72 hours CIALIS for once daily use: dose not to exceed 2.5 mg CYP3A4 inducers (e.g. rifampin) decrease CIALIS exposure ( 7.2 ). (Tadalafil label, Drug interactions)

  • Telmisartan and amlodipineangiotensin II receptor blocker (ARB)Moderate

    Patients should be monitored for adequate clinical effect when amlodipine is co-administered with CYP3A4 inducers. (Telmisartan and amlodipine label, Drug interactions)

  • TemsirolimusModerate

    Co-administration with Inducers or Inhibitors of CYP3A Metabolism Agents Inducing CYP3A Metabolism: Strong inducers of CYP3A4/5 such as dexamethasone, carbamazepine, phenytoin, phenobarbital, rifampin, rifabutin, and rifampacin may decrease exposure of the active metabolite, sirolimus. (Temsirolimus label, Warnings and precautions)

  • TerbinafineantifungalModerate

    Terbinafine clearance is increased 100% by rifampin, a CYP450 enzyme inducer, and decreased 33% by cimetidine, a CYP450 enzyme inhibitor. (Terbinafine label, Drug interactions)

  • TheophyllinemethylxanthineModerate

    30% increase Phenobarbital (PB) Similar to aminoglutethimide. (Theophylline label, Drug interactions)

  • TiagabineanticonvulsantModerate

    Use of tiagabine HCl without enzyme-inducing antiepileptic drugs results in blood levels about twice those attained in the studies on which current dosing recommendations are based (see DOSAGE AND ADMINISTRATION ). (Tiagabine label, Warnings)

  • TinidazoleantibioticModerate

    Phenytoin, fosphenytoin: Adjustment of anticonvulsant and/or tinidazole dose(s) may be needed ( 7.1, 7.2 ) (Tinidazole label, Drug interactions)

  • TofacitinibimmunosuppressantModerate

    …exposure to tofacitinib Intervention Dosage modification of XELJANZ/XELJANZ XR is recommended [see Dosage and Administration (2) , Clinical Pharmacology, Figure 3 (12.3) ] Strong CYP3A4 Inducers (e.g., rifampin) Clinical Impact Decreased exposure to tofacitinib and may result in loss of or reduced clinical response Intervention Concomitant use with XELJANZ/XELJANZ… (Tofacitinib label, Drug interactions)

  • TopiramateanticonvulsantModerate

    Because of the potential of topiramate to cause CNS depression, as well as other cognitive and/or neuropsychiatric adverse reactions, topiramate extended-release capsules should be used with extreme caution if used in combination with alcohol and other CNS depressants. (Topiramate label, Drug interactions)

  • TranylcypromineMAO inhibitorModerate

    Excessive reduction of blood glucose (additive effect) f CNS depressant agents (including opioids, alcohol, sedatives, hypnotics) Use with caution d Increased CNS depression Dietary supplements containing sympathomimetics Contraindicated a Antidepressants including but not limited to: Other MAOIs (e.g., linezolid, intravenous methylene blue, selective MAOIs)… (Tranylcypromine label, Drug interactions)

  • Treprostinilprostaglandin analogModerate

    Co-administration of a CYP2C8 enzyme inducer (e.g., rifampin) may decrease exposure to treprostinil. (Treprostinil label, Warnings and precautions)

  • TriamcinolonecorticosteroidModerate

    Hepatic enzyme inducers (e.g., barbiturates, phenytoin, carbamazepine, rifampin): Drugs which induce hepatic microsomal drug metabolizing enzyme activity may enhance the metabolism of corticosteroids and require that the dosage of the corticosteroid be increased. (Triamcinolone label, Drug interactions)

  • TrihexyphenidylanticholinergicModerate

    Drug Interactions Cannabinoids, barbiturates, opiates, and alcohol may have additive effects with trihexyphenidyl, and thus, an abuse potential exists. (Trihexyphenidyl label, Drug interactions)

  • The recent use of other drugs that cause CNS depression or EPS symptoms may also increase the risk; consider reducing the dosage or discontinuing the drug. (Trimethobenzamide label, Warnings and precautions)

  • Vecuroniumneuromuscular blockerModerate

    Thiopental Reconstituted vecuronium, which has an acid pH, should not be mixed with alkaline solutions (e.g., barbiturate solutions such as thiopental) in the same syringe or administered simultaneously during intravenous infusion through the same needle or through the same intravenous line (see DOSAGE AND ADMINISTRATION -COMPATIBILITY ). (Vecuronium label, Precautions)

  • Verapamilcalcium channel blockerModerate

    Phenobarbital Phenobarbital therapy may increase verapamil clearance. (Verapamil label, Drug interactions)

  • VilazodoneSSRIModerate

    CYP3A4 Inducers: Consider increasing VIIBRYD dosage by 2-fold, up to 80 mg once-daily over 1 to 2 weeks when used concomitantly with strong CYP3A4 inducers for greater than 14 days ( 2.4 , 7 ). (Vilazodone label, Drug interactions)

  • VincristineModerate

    Drug Interactions The simultaneous oral or intravenous administration of phenytoin and antineoplastic chemotherapy combinations that included vincristine sulfate has been reported to reduce blood levels of the anticonvulsant and to increase seizure activity. (Vincristine label, Drug interactions)

  • WarfarinanticoagulantModerate

    …etravirine, fluconazole, fluvastatin, fluvoxamine, metronidazole, miconazole, oxandrolone, sulfinpyrazone, tigecycline, voriconazole, zafirlukast aprepitant, bosentan, carbamazepine, phenobarbital, rifampin CYP1A2 acyclovir, allopurinol, caffeine, cimetidine, ciprofloxacin, disulfiram, enoxacin, famotidine, fluvoxamine, methoxsalen, mexiletine, norfloxacin, oral… (Warfarin label, Drug interactions)

  • ZonisamideanticonvulsantModerate

    Patients should be carefully observed for signs of central nervous system (CNS) depression, such as somnolence and sedation, when ZONISADE is used with other drugs with sedative properties because of potential additive effects. (Zonisamide label, Warnings and precautions)

Minor mentions (23)

  • Concomitant taking of P-gp inducers (including but not limited to rifampicin, carbamazepine, phenytoin, phenobarbital, and St. (Afatinib label, Drug interactions)

  • Atracuriumneuromuscular blockerMinor

    Atracurium besylate injection, which has an acid pH, should not be mixed with alkaline solutions (e.g., barbiturate solutions) in the same syringe or administered simultaneously during intravenous infusion through the same needle. (Atracurium label, Warnings)

  • CefazolincephalosporinMinor

    Anticonvulsant therapy should be continued in patients with known seizure disorders. (Cefazolin label, Warnings and precautions)

  • CephalexincephalosporinMinor

    Anticonvulsant therapy can be given if clinically indicated. (Cephalexin label, Warnings and precautions)

  • CidofovirantiviralMinor

    …Probenecid Probenecid is known to interact with the metabolism or renal tubular excretion of many drugs (e.g., acetaminophen, acyclovir, angiotensin-converting enzyme inhibitors, aminosalicylic acid, barbiturates, benzodiazepines, bumetanide, clofibrate, methotrexate, famotidine, furosemide, nonsteroidal anti-inflammatory agents, theophylline, and zidovudine). (Cidofovir label, Drug interactions)

  • DextroamphetamineCNS stimulantMinor

    Antihistamines Amphetamines may counteract the sedative effect of antihistamines. (Dextroamphetamine label, Drug interactions)

  • • Cytochrome P450 3A4 inducers, inhibitors, or substrates: May alter docetaxel metabolism. (Docetaxel label, Drug interactions)

  • DolutegravirantiretroviralMinor

    Use alternative treatment that does not include carbamazepine where possible for INSTI-experienced patients with certain INSTI-associated resistance substitutions or clinically suspected INSTI resistance. b Oxcarbazepine Phenytoin Phenobarbital St. (Dolutegravir label, Drug interactions)

  • In Drug-Induced CNS and Respiratory Depression Doxapram alone may not stimulate adequate spontaneous breathing or provide sufficient arousal in patients who are severely depressed either due to respiratory failure or to CNS depressant drugs, but may be used as an adjunct to established supportive measures and resuscitative techniques. (Doxapram label, Warnings)

  • The “gasping syndrome” is characterized by central nervous system (CNS) depression, metabolic acidosis, and gasping respirations. (Epoetin alfa label, Warnings and precautions)

  • Effects of Other Drugs on HALAVEN No drug-drug interactions are expected with CYP3A4 inhibitors, CYP3A4 inducers or P-glycoprotein (P-gp) inhibitors. (Eribulin label, Drug interactions)

  • EthosuximideanticonvulsantMinor

    Data are more extensive with respect to phenytoin and phenobarbital, but these are also the most commonly prescribed anticonvulsants; less systematic or anecdotal reports suggest a possible similar association with the use of all known anticonvulsant drugs. (Ethosuximide label, Warnings)

  • A similar association, though less marked, has been suggested for barbiturates, phenylbutazone, phenytoin sodium, and possibly with griseofulvin, ampicillin, and tetracyclines. (Ethynodiol diacetate and ethinyl estradiol label, Drug interactions)

  • Potential for Glycerol Phenylbutyrate to Affect Other Drugs Drugs with narrow therapeutic index that are substrates of CYP3A4 Glycerol phenylbutyrate is a weak inducer of CYP3A4 in humans. (Glycerol phenylbutyrate label, Drug interactions)

  • KetorolacNSAIDMinor

    Antiepileptic Drugs Sporadic cases of seizures have been reported during concomitant use of ketorolac tromethamine and antiepileptic drugs (phenytoin, carbamazepine). (Ketorolac label, Drug interactions)

  • LevetiracetamanticonvulsantMinor

    Other Antiepileptic Drugs Potential drug interactions between levetiracetam and other AEDs (carbamazepine, gabapentin, lamotrigine, phenobarbital, phenytoin, primidone and valproate) were also assessed by evaluating the serum concentrations of levetiracetam and these AEDs during placebo-controlled clinical studies. (Levetiracetam label, Drug interactions)

  • Anticonvulsants, psychotropic, hormone preparations, corticosteroids, antithyroid agents, cyproheptadine: may affect the results of the metyrapone test. (Metyrapone label, Drug interactions)

  • MexiletineantiarrhythmicMinor

    When phenytoin or other hepatic enzyme inducers such as rifampin and phenobarbital have been taken concurrently with mexiletine, lowered mexiletine plasma levels have been reported. (Mexiletine label, Drug interactions)

  • Prazosinalpha blockerMinor

    …glycosides– digitalis and digoxin; (2) hypoglycemics–insulin, chlorpropamide, phenformin, tolazamide, and tolbutamide; (3) tranquilizers and sedatives–chlordiazepoxide, diazepam, and phenobarbital; (4) antigout–allopurinol, colchicine, and probenecid; (5) antiarrhythmics–procainamide, propranolol (see WARNINGS however), and quinidine; and (6) analgesics, antipyretics… (Prazosin label, Drug interactions)

  • RaltegravirantiretroviralMinor

    The impact of other inducers of drug metabolizing enzymes, such as phenytoin and phenobarbital, on UGT1A1 is unknown. (Raltegravir label, Drug interactions)

  • RifaximinantibioticMinor

    CYP3A4 Substrates An in vitro study has suggested that rifaximin induces CYP3A4 [see Clinical Pharmacology ( 12.3 )] . (Rifaximin label, Drug interactions)

  • RiociguatvasodilatorMinor

    Strong CYP3A inducers: Strong inducers of CYP3A (for example, rifampin, phenytoin, carbamazepine, phenobarbital or St. (Riociguat label, Drug interactions)

  • These data suggest that GH may alter the clearance of compounds known to be metabolized by CYP450 liver enzymes (e.g., corticosteroids, sex steroids, anticonvulsants, and cyclosporine). (Tesamorelin label, Drug interactions)

No significant interaction reported (3)

  • Losartanangiotensin II receptor blocker (ARB)No interaction

    Drug Interactions No clinically significant drug interactions have been found in studies of losartan potassium with hydrochlorothiazide, digoxin, warfarin, cimetidine and phenobarbital. (Losartan label, Drug interactions)

  • MicafunginantifungalNo interaction

    CYP2C19 and CYP3A4 Inducer Co-administration of Micafungin in Sodium Chloride Injection with rifampin and ritonavir did not alter the pharmacokinetics of micafungin. (Micafungin label, Drug interactions)

  • Montelukastleukotriene receptor antagonistNo interaction

    …adjustment is needed when SINGULAIR is co-administered with theophylline, prednisone, prednisolone, oral contraceptives, fexofenadine, digoxin, warfarin, gemfibrozil, itraconazole, thyroid hormones, sedative hypnotics, non-steroidal anti-inflammatory agents, benzodiazepines, decongestants, and Cytochrome P450 (CYP) enzyme inducers [see Clinical Pharmacology (12.3) ]. (Montelukast label, Drug interactions)

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