St. John's Wort (Hypericum perforatum) is a flowering plant historically used in traditional European medicine. It is commonly taken as an herbal supplement, primarily recognized for its potential effects on mood. The plant's extract contains several active compounds, including hypericin and hyperforin, which are thought to contribute to its activity. The use of St. John's Wort for various conditions has been extensively studied, particularly in relation to mood support. It is available in various forms, including capsules, tablets, teas, and liquid extracts (National Center for Complementary and Integrative Health (NCCIH)).
Deep dive
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Known interactions
Category rule: glp1 × supplement
Note
GLP-1 medications slow stomach emptying, changing how/when oral supplements absorb; rapid weight loss raises the importance of protein and micronutrients.
Time oral supplements when nausea is lowest; prioritize protein and micronutrients; discuss with your provider.
Category rule: supplement × medication
Note
Some supplements change how the body processes medications (absorption, liver enzymes, or additive effects).
Specific pairs are checked against a licensed drug database and shown with their own severity. Always confirm with your provider or pharmacist.
Compound-pair rule
Avoid
St John's Wort has serotonergic activity and induces CYP3A4, altering SSRI levels.
Avoid combining.
Compound-pair rule
Avoid
St John's Wort has serotonergic activity and induces CYP3A4, altering SSRI levels.
Avoid combining.
Compound-pair rule
Avoid
St John's Wort has serotonergic activity and induces CYP3A4, altering SSRI levels.
Avoid combining.
Compound-pair rule
Avoid
St John's Wort has serotonergic activity and induces CYP3A4, altering SSRI levels.
Avoid combining.
Compound-pair rule
Avoid
St John's Wort has serotonergic activity and induces CYP3A4, altering SSRI levels.
Avoid combining.
Compound-pair rule
Caution
St Johns wort is serotonergic and CNS-active; theoretical additive stimulation with amantadine.
Avoid combining unless cleared by your clinician.
Frequently asked
Sources referenced
- National Center for Complementary and Integrative Health (NCCIH)
- National Institutes of Health (NIH) Office of Dietary Supplements (ODS)
- MedlinePlus
- Mayo Clinic
- DrugBank
- PubChem
- Cochrane Library
- Examine.com
- European Medicines Agency (EMA) SmPC
- Journal of Clinical Psychiatry (Peer-reviewed literature)
DoseRoutine compiles summaries from publicly available scientific and regulatory references. Always verify important decisions with a licensed clinician.
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