Butalbital, aspirin, caffeine, and codeine and Fosphenytoin interaction
Butalbital, aspirin, caffeine, and codeine and Fosphenytoin: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Butalbital, aspirin, caffeine, and codeine (BUTALBITAL, ASPIRIN, CAFFEINE and CODEINE PHOSPHATE) label · effective 2026-01-15
Concomitant use of opioids or a barbiturate with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death.
The effects of concomitant use or discontinuation of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complex.
Use of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with BUTALBITAL, ASPIRIN, CAFFEINE and CODEINE PHOSPHATE requires careful consideration of the effects on codeine, and the active metabolite, morphine.
Risks From Concomitant Use With Benzodiazepines Or Other CNS Depressants Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death.
Reserve concomitant prescribing of BUTALBITAL, ASPIRIN, CAFFEINE and CODEINE PHOSPHATE and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate. [see Warnings and Precautions ( 5.3 , 5.9 ), Drug Interactions ( 7 )].
From the Fosphenytoin (CEREBYX) label · effective 2025-08-28
Additionally, consider alternatives to structurally similar drugs such as carboxamides (e.g., carbamazepine), barbiturates, succinimides, and oxazolidinediones (e.g., trimethadione) in these same patients.
…sulfamethoxazole-trimethoprim Other Acute alcohol intake, amiodarone, chloramphenicol, chlordiazepoxide, disulfiram, estrogen, fluvastatin, isoniazid, methylphenidate, phenothiazines, salicylates, ticlopidine, tolbutamide, trazodone, warfarin Drugs that may decrease phenytoin serum levels Antineoplastic agents usually in combination Bleomycin, carboplatin, cisplatin,…
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).
Other Corticosteroids, doxycycline, estrogens, furosemide, oral contraceptives, paroxetine, quinidine, rifampin, sertraline, theophylline, and vitamin D Drugs whose level is decreased by phenytoin Anticoagulants Apixaban, dabigatran, edoxaban, rivaroxaban Antiepileptic drugs The effect of phenytoin on phenobarbital, valproic acid and sodium valproate serum levels…
Carbamazepine, felbamate, lamotrigine, topiramate, oxcarbazepine, lacosamide Antiplatelets Ticagrelor Antilipidemic agents Atorvastatin, fluvastatin, simvastatin Antiviral agents Efavirenz, lopinavir/ritonavir, indinavir, nelfinavir, ritonavir, saquinavir Fosamprenavir: phenytoin when given with fosamprenavir alone may decrease the concentration of amprenavir,…
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.