bexarotene and Ethynodiol Interactions

Interactions between bexarotene and Ethynodiol (ethynodiol)

ethynodiol and bexarotene (Major Drug-Drug)

ADDITIONAL CONTRACEPTION RECOMMENDED: There are no data concerning the potential effect of bexarotene on hormonal contraceptives. Presumably, coadministration with bexarotene may decrease the efficacy of contraceptives containing low-dose estrogens and progestins due to its induction of CYP450 3A4, the isoenzyme that is primarily responsible for the metabolic clearance of sex hormones.

MANAGEMENT: Women using low-dose hormonal contraceptives should be advised of the risk of breakthrough bleeding and unintended pregnancy during concomitant therapy with bexarotene. Because use of bexarotene is likely associated with major birth defects, it is particularly important that patients not become pregnant during treatment. Therefore, hormonal contraceptives should not be used as the sole method of birth control in women of childbearing potential treated with bexarotene. Product labeling recommends that two reliable forms of contraception, one non-hormonal, be used simultaneously during bexarotene therapy and for at least one month following discontinuation of therapy. Input from a gynecologist or similar expert on adequate contraception should be sought as needed. Intrauterine systems are unlikely to be significantly affected because of their local action.