Interactions with other medications
Effects of phenobarbital on other drugs
Because phenobarbital accelerates hepatic metabolism, it will increase the clearance of:
- oral contraceptives
- valproate
- phenytoin
- primidone
- carbamazepine
- topiramate
- lamotrigine
- tiagabine
- zonisamide
- theophylline
- warfarin
- steroids
Effects of other drugs on Phenobarbital
Valproate will increase the serum concentration of phenobarbital by inhibiting its hepatic metabolism.
On the other hand, drugs that accelerate hepatic metabolism will lower serum concentrations of phenobarbital. These include:
- phenytoin
- carbamazepine
- primidone
- oxcarbazepine
- felbamate
AED Interaction Sheets:
Seizure drugs are often affected by drug-drug interactions. Print these informative sheets for practical help.
