<p>Concurrent use of the following drugs may result in reduced efficacy of this tablet and increased incidence of breakthrough bleeding: Ampicillin, Analgesics, Antihistamines, Antimigraine preparations, Chloramphenicol, Griseofulvin, Isoniazid, Neomycin, Nitrofurantain, Penicillin V, Phenylbutazone, Sulfonamides and Tetracycline.<br />
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Concurrent use of anticoagulants with estrogen/progestogen combinations may reduce the anticoagulant effect. Effectiveness of the following drugs may be altered when used concurrently: Antihypertensive, Benzodiazepines (those that undergo oxidative degradation), Beta-adrenergic blockers,Caffeine, Corticosteroids, Hypoglycemic, Phenothiazine, Theophylline, Tricyclic antidepressants and Vitamins.<br />
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Concurrent use of the following drugs may reduce the efficacy of this tablet because of accelerated estrogen metabolism caused by the induction of hepatic enzymes: Carbamazepine, Phenobarbital, Phenytoin, Pyrimidine and Rifampicin.<br />
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Diabetics using estrogen/progestogen combinations may require adjustment of their antidiabetic medication. Concurrent administration of vitamin C (ascorbic acid) with estrogen/ progestogen combinations has been reported to result in a significant rise in plasma Ethinylestradiol levels.<br />
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Rule out pregnancy before treatment is begun. Because of the antiandrogenic action of this tablet,feminization of male fetuses has occurred in animal studies and may possibly occur in humans.</p>