Can you take 5-HTP and St. John's Wort together?
Do not combine. Both raise serotonin through different mechanisms, creating a risk of serotonin syndrome — a potentially life-threatening condition.
Severity
Avoid
Evidence
strong
Timing
Do not combine.
How it works
5-HTP is a direct serotonin precursor while St. John's Wort inhibits serotonin reuptake, producing additive serotonergic effects.
Serotonin syndrome symptoms include agitation, rapid heartbeat, high blood pressure, dilated pupils, and in severe cases, hyperthermia and seizures. The risk is analogous to combining an SSRI with a serotonin precursor.
What to do
Choose one or the other, never both. If switching between them, allow a 2-week washout period for St. John's Wort to clear your system.
Frequently asked
Should I separate 5-HTP and St. John's Wort?
Yes. This combination should be avoided. Risk of serotonin syndrome Consult a healthcare professional before combining these supplements.
Why do 5-HTP and St. John's Wort interact?
5-HTP is a direct serotonin precursor while St. John's Wort inhibits serotonin reuptake, producing additive serotonergic effects.
How strong is the evidence for this interaction?
The evidence is strong, supported by multiple published studies and clinical data.
About these supplements
Other 5-HTP interactions
Other St. John's Wort interactions
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This information is for educational purposes only. It is not medical advice and does not diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional.