Taking drugs for infection (such as ampicillin, chloramphenicol, neomycin, penicillin V, nitrofurantoin, sulfonamides, tetracycline and isoniazid) and pain (analgesic, anti-migraine and tranquilizer) with contraceptive pill may decrease the contraceptive's efficacy. If patient is advised to take the drugs mentioned previously, consult a healthcare provider for proper intake and dosage schedule of the contraceptive pill.
Taking contraceptive pills and anti-infective drugs (such as clarithromycin, erythromycin,, itraconazole, ketoconazole, ritonavir) or grapefruit juice may inhibit cytochrome P-450 isoenzyme 3A4. Adverse effects may be seen after taking these drugs.
Taking oral contraceptive pills and drugs that induce hepatic enzyme production such as anti-epileptic drugs (carbamazepine, oxcarbazepine, felbamate, topiramate, phenytoin), antifungal (griseofulvin), anti-diabetic (troglitazone), musculoskeletal (phenylbutazone), and anti-tuberculosis (rifampicin) drugs can considerably reduce the contraceptive's efficacy.
Taking contraceptives and troleandomycin may increase the risk of cholestatic jaundice.