- CYP3A4 inducing agents; patients receiving the following CYP3A4 inducing agents will be excluded; these include: carbamazepine, ethosuximide, griseofulvin, modafinil, nafcillin, oxcarbazepine, Phenobarbital, phenylbutazone, phenytoin, rifampin, rifabutin, St. John's Wort, and sulfinpyrazone