Can you take Melatonin and St. John's Wort together?
St. John's Wort induces CYP1A2, the enzyme that breaks down melatonin. Long-term SJW use can reduce both endogenous and supplemental melatonin levels.
Severity
Caution
Evidence
moderate
Timing
SJW morning, melatonin bedtime.
How it works
SJW induces CYP1A2, the primary enzyme responsible for melatonin hepatic metabolism.
The enzyme induction can reduce melatonin's half-life and peak levels. This may explain why some SJW users report sleep disturbances. The effect builds over weeks of SJW use as enzyme induction accumulates.
What to do
If you take both, you may need a higher melatonin dose to achieve the same effect. Take SJW in the morning, melatonin at bedtime. Monitor sleep quality.
Frequently asked
Should I separate Melatonin and St. John's Wort?
Consider separating them. SJW morning, melatonin bedtime. Consult a healthcare professional for personalised advice.
Why do Melatonin and St. John's Wort interact?
SJW induces CYP1A2, the primary enzyme responsible for melatonin hepatic metabolism.
How strong is the evidence for this interaction?
The evidence is moderate. Some studies support this interaction, but more research may be needed.
About these supplements
Other Melatonin 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.