Interaction Checker

Methylnaltrexone interactions

Methylnaltrexone (Relistor), an opioid antagonist has 52 documented interactions across the FDA labels and fact sheets we index: 43 major, 2 moderate, 0 minor, and 7 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 (43)

  • Acetaminophen and codeineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Alvimopanopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Belladonna and opiumopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Bictegravir, emtricitabine, and tenofovir alafenamideantiretroviralMajor

    Opioid Antagonist: Naloxegol ↑ naloxegol Avoid use with BIXLENVO; if unavoidable, decrease the dosage of naloxegol and monitor for adverse reactions. (Bictegravir, emtricitabine, and tenofovir alafenamide label, Drug interactions)

  • BuprenorphineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Buprenorphine and naloxoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Butalbital, acetaminophen, caffeine, and codeinebarbiturateMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Butalbital, aspirin, caffeine, and codeinebarbiturateMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • ButorphanolopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • CodeineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • DarunavirantiretroviralMajor

    John's wort ( Hypericum perforatum ) Hepatitis C direct acting antiviral: 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… (Darunavir label, Contraindications)

  • Darunavir and cobicistatantiretroviralMajor

    John's wort ( Hypericum perforatum ) Hepatitis C direct acting antiviral: 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 PREZCOBIX or PREZCOBIX PED is… (Darunavir and cobicistat label, Contraindications)

  • EluxadolineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • FentanylopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • HydrocodoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Hydrocodone and acetaminophenopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Hydrocodone and chlorpheniramineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Hydrocodone and homatropineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Hydrocodone and ibuprofenopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • HydromorphoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • LenacapavirantiretroviralMajor

    Opioid Antagonist: naloxegol ↑ naloxegol Avoid use with SUNLENCA; if unavoidable, decrease the dosage of naloxegol and monitor for adverse reactions. (Lenacapavir label, Drug interactions)

  • LevorphanolopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • MeperidineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • MethadoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • MorphineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • NalbuphineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Naldemedineopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Nalmefeneopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Naloxegolopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Naloxoneopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Naltrexoneopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Naltrexone and bupropionopioid antagonistMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Nirmatrelvir and ritonavirantiviralMajor

    …Migraine medications: eletriptan, ubrogepant • Mineralocorticoid receptor antagonists: finerenone • Non-opioid analgesic (selective blocker of Na v 1.8 sodium channels): suzetrigine • Opioid antagonists: naloxegol • PDE5 inhibitor: sildenafil (Revatio ® ) when used for pulmonary arterial hypertension (PAH) • Sedative/hypnotics: triazolam, oral midazolam • Serotonin… (Nirmatrelvir and ritonavir label, Contraindications)

  • OliceridineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • OxycodoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Oxycodone and acetaminophenopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • OxymorphoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Pentazocine and naloxoneopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Promethazine and codeineopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • RemifentanilopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • TapentadolopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • TramadolopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

  • Tramadol and acetaminophenopioidMajor

    • Other Opioid Antagonists : Potential for additive effect and increased risk of opioid withdrawal; avoid concomitant use. (Methylnaltrexone label, Drug interactions)

Moderate interactions (2)

  • EtravirineantiretroviralModerate

    Narcotic analgesics/treatment of opioid dependence: buprenorphine buprenorphine/naloxone methadone ↔ etravirine ↓ buprenorphine ↔ norbuprenorphine ↔ methadone Etravirine and buprenorphine (or buprenorphine/naloxone) can be co-administered without dose adjustments, however, clinical monitoring for withdrawal symptoms is recommended as buprenorphine (or buprenorphine/naloxone)… (Etravirine label, Drug interactions)

  • Lofexidinealpha-adrenergic agonistModerate

    Oral Naltrexone : Concomitant use may reduce efficacy of oral naltrexone. (Lofexidine label, Drug interactions)

No significant interaction reported (7)

  • AcamprosateNo interaction

    The pharmacokinetics of acamprosate are not affected by alcohol, diazepam, or disulfiram, and clinically important interactions between naltrexone and acamprosate were not observed [ see Clinical Pharmacology ( 12.3 ) ]. (Acamprosate label, Drug interactions)

  • Brompheniramine, pseudoephedrine, and dextromethorphanantihistamineNo interaction

    Drugs Metabolized by Cytochrome P450 Isozymes In healthy subjects, a subcutaneous dose of 0.3 mg/kg of RELISTOR did not significantly affect the metabolism of dextromethorphan, a CYP2D6 substrate. (Methylnaltrexone label, Drug interactions)

  • Dextromethorphanserotonergic drugNo interaction

    Drugs Metabolized by Cytochrome P450 Isozymes In healthy subjects, a subcutaneous dose of 0.3 mg/kg of RELISTOR did not significantly affect the metabolism of dextromethorphan, a CYP2D6 substrate. (Methylnaltrexone label, Drug interactions)

  • Dextromethorphan and quinidineserotonergic drugNo interaction

    Drugs Metabolized by Cytochrome P450 Isozymes In healthy subjects, a subcutaneous dose of 0.3 mg/kg of RELISTOR did not significantly affect the metabolism of dextromethorphan, a CYP2D6 substrate. (Methylnaltrexone label, Drug interactions)

  • Elvitegravir, cobicistat, emtricitabine, and tenofovirantiretroviralNo interaction

    Narcotic Analgesics: buprenorphine/ naloxone ↑ buprenorphine ↑ norbuprenorphine ↓ naloxone No dosage adjustment of buprenorphine/naloxone is required upon coadministration with GENVOYA. (Elvitegravir, cobicistat, emtricitabine, and tenofovir label, Drug interactions)

  • Emtricitabine and tenofovirantiretroviralNo interaction

    No clinically significant drug interactions have been either observed or are expected when DESCOVY is combined with the following drugs: buprenorphine, itraconazole, ketoconazole, lorazepam, methadone, midazolam, naloxone, norbuprenorphine, norgestimate/ethinyl estradiol, and sertraline. (Emtricitabine and tenofovir label, Drug interactions)

  • Promethazine and dextromethorphanantihistamineNo interaction

    Drugs Metabolized by Cytochrome P450 Isozymes In healthy subjects, a subcutaneous dose of 0.3 mg/kg of RELISTOR did not significantly affect the metabolism of dextromethorphan, a CYP2D6 substrate. (Methylnaltrexone label, Drug interactions)

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Not medical advice. Severity reflects the label's wording, not your circumstances. A "major" flag can be routine under supervision and a "minor" one can matter at high doses. Ask a pharmacist.