Rifamycin antibakterielle midler (rifampicin, rifabutin), visse antiepileptika (phenytoin, carbamazepin, phenobarbital, primidon), efavirenz og cimetidin:
Rifamycin antibacterials (rifampicin, rifabutin), certain anticonvulsants (phenytoin, carbamazepine, phenobarbital, primidone), efavirenz and cimetidine: