MAJOR — Use With Caution
🔴 CAUTION — Major interaction between St. Johns Wort and Combined Oral Contraceptives. Avoid unless under direct medical supervision.
Evidence level: STRONG
St. John's Wort can make birth control pills STOP WORKING. It speeds up hormone breakdown, potentially leading to unintended pregnancy.
St. John's Wort potently induces CYP3A4 and P-glycoprotein, accelerating metabolism of ethinyl estradiol and progestins, reducing blood levels by up to 50%.
St. Johns Wort affects how your body processes Combined Oral Contraceptives, which may change its effectiveness. Your doctor may need to adjust dosages or consider an alternative. Do not change doses on your own.
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. St. Johns Wort can be taken at any convenient time.
Higher risk with: liver impairment, genetic CYP enzyme variations (poor or ultra-rapid metabolizers), older age, polypharmacy (many medications).
Monitor for any unusual symptoms and report them to your healthcare provider promptly.
Ask your doctor: "Is there a safer alternative to St. Johns Wort that I can take with Combined Oral Contraceptives?" Bring a list of ALL supplements and medications you take.
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.
St. John's Wort can make birth control pills STOP WORKING. It speeds up hormone breakdown, potentially leading to unintended pregnancy.
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. St. Johns Wort can be taken at any convenient time.
Monitor for any unusual symptoms and report them to your healthcare provider promptly.
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.
Ask your doctor: "Is there a safer alternative to St. Johns Wort that I can take with Combined Oral Contraceptives?" Bring a list of ALL supplements and medications you take.
Or browse the full interaction database (121,000+ pairs).