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Medicines st johns wortQuestion & answer

st johns wort · Medicine question

Does St John’s wort affect contraception?

iatroX medicinesPublished 21 August 2026Reviewed 21 August 2026

The answer

Answer

Yes. It can reduce the effectiveness of hormonal contraception and increase the risk of breakthrough bleeding and unintended pregnancy.

Sources for this answer

Care St John's Wort Low Mood Relief Tablets / UCalm St John's Wort Tabletsemc · SmPC Current selected SmPC · Version 2
NHS Specialist Pharmacy ServiceNHS Specialist Pharmacy Service · NHS medicine guidance

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st johns wort

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