<unk>  is an inducer of the CYP3A4 and CYP2C9 families of the P450 enzyme responsible for the liver's degradation of various drugs. A 1981 study by the National Institutes of Health showed that antacids administered concomitantly with<unk>  "altered not only the extent of absorption but also appeared to alter the rate of absorption. Antacids administered in a peptic ulcer regimen may decrease the AUC of a single dose of<unk> . Patients should be cautioned against concomitant use of antacids and<unk> ." Warfarin and trimethoprim increase serum<unk>  levels and prolong the serum half-life of<unk>  by inhibiting its metabolism. Consider using other options if possible.
Phenytoin
Mephenytoin
Carbamazepine
Mesuximide
Propazepine
Levetiracetam
Phenobarbital
Oxcarbazepine