Concomitant use w/ ritonavir, phenytoin, carbamazepine, phenobarb, primidone, aspirin, carbapenem antibiotics, colestyramine, oestrogen-containing hormonal contraceptive, felbamate, metamizole, MTX, lopinavir, rifampicin, amitriptyline/nortriptyline, carbamazepine-10,11-epoxide, clonazepam, diazepam, ethosuximide, lamotrigine, cefditoren pivoxil, adefovir dipivoxil, pivmecillinam, pivampicillin, primidone, propofol, nimodipine, tolbutamide, cannabidiol, topiramate, acetazolamide, warfarin, zidovudine, quetiapine, lorazepam, olanzapine, rufinamide, steroid-containing OC.