Herbs
St John's wort
Also called: hypericum, St. John's wort
A flowering plant used for mood.
- Why people take it
- Mild to moderate depression.
- What the evidence says
- Works better than placebo for mild depression in some studies.
- How it is usually taken
- Extracts of 300 mg three times a day were used in studies.
- Be careful
- Interacts with many medicines: birth control pills, antidepressants, HIV drugs, blood thinners, transplant drugs. Never combine without a doctor.
- Medicines it can interact with
- Makes many medicines stop working: the contraceptive pill, warfarin, ciclosporin, HIV medicines, some heart and cancer medicines. Serotonin syndrome with antidepressants. Talk to a doctor before taking it with ANY medicine.
Other herbs
Common questions
What is St John's wort?
A flowering plant used for mood.
Why do people take St John's wort?
Mild to moderate depression.
Does St John's wort work?
Works better than placebo for mild depression in some studies.
How much St John's wort do people take?
Extracts of 300 mg three times a day were used in studies.
Is St John's wort safe?
Interacts with many medicines: birth control pills, antidepressants, HIV drugs, blood thinners, transplant drugs. Never combine without a doctor.
Does St John's wort interact with medicines?
Makes many medicines stop working: the contraceptive pill, warfarin, ciclosporin, HIV medicines, some heart and cancer medicines. Serotonin syndrome with antidepressants. Talk to a doctor before taking it with ANY medicine.
Sources and further reading
Last reviewed 31 October 2026. Written by Satya Babu.
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