MODERATE — Monitor Closely
CAUTION — possible hormonal interaction; monitor
Evidence level: LIMITED
Black cohosh may interact with birth control hormones, though the clinical importance is uncertain.
Black cohosh may have estrogenic activity that could interact with hormonal contraceptives, though clinical significance is debated.
Inform your prescriber. Monitor for breakthrough bleeding or side effects.
Take Combined Oral Contraceptives at the same time every day. CRITICAL: St. John's Wort induces CYP3A4 and can reduce contraceptive hormone levels enough to cause failure — breakthrough bleeding is a warning sign. Other botanicals are generally safe. Black Cohosh can be taken at any convenient time.
History of estrogen-sensitive conditions
Breakthrough bleeding, breast tenderness, headaches
Mention black cohosh use to gynecologist.
Some substances can reduce contraceptive effectiveness. Use backup contraception if adding a known CYP3A4 inducer. Discuss with your gynecologist — IUDs and injections are not affected by enzyme-inducing interactions.
Black cohosh may interact with birth control hormones, though the clinical importance is uncertain.
Take Combined Oral Contraceptives at the same time every day. CRITICAL: St. John's Wort induces CYP3A4 and can reduce contraceptive hormone levels enough to cause failure — breakthrough bleeding is a warning sign. Other botanicals are generally safe. Black Cohosh can be taken at any convenient time.
Breakthrough bleeding, breast tenderness, headaches
Some substances can reduce contraceptive effectiveness. Use backup contraception if adding a known CYP3A4 inducer. Discuss with your gynecologist — IUDs and injections are not affected by enzyme-inducing interactions.
Mention black cohosh use to gynecologist.
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