Phenobarbital, hyoscyamine, atropine, and scopolamine and Phenytoin interaction
Phenobarbital, hyoscyamine, atropine, and scopolamine and Phenytoin: the Phenytoin prescribing label describes an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Phenytoin label · effective 2024-12-24
John’s wort may vary widely based on preparation. , sucralfate, theophylline Drugs that may either increase or decrease phenytoin serum levels Antiepileptic drugs Phenobarbital, valproate sodium Valproate sodium and valproic acid are similar medications.
…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 is unpredictable.
Additionally, consider alternatives to structurally similar drugs such as carboxamides (e.g., carbamazepine), barbiturates, succinimides, and oxazolidinediones (e.g., trimethadione) in these same patients.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.