5-HTP + St. John's Wort

Can you take 5-HTP and St. John's Wort together?

CriticalMechanism-based

No — don't combine two serotonin-raising supplements.

What to do. Choose one, and never combine either with antidepressants without medical advice.

Mechanism

Serotonin syndrome risk

5-HTP is converted directly into serotonin, and St. John's wort increases serotonin signaling. Together they can cause serotonin toxicity: agitation, fast heart rate, high temperature, muscle twitching.

Evidence: Mechanism-based — Plausible biological mechanism with little direct human outcome data.

  1. 01NIH NCCIH — St. John's Wort
  2. 02Maffei ME. 5-Hydroxytryptophan (5-HTP): natural occurrence, analysis, biosynthesis, biotechnology, physiology and toxicology. Int J Mol Sci 2020.

Timing

A day with 5-HTP and St. John's Wort

  1. 08:00

    Breakfast

    with meal
  2. 22:30

    Bedtime

    no food

Taking more than these two?

Add the rest of your stack and your medications for a complete check.

Check my full stack

Buying guide

What to look for on the label

  • 5-HTP

    • Griffonia simplicifolia extract from a tested brand

  • St. John's Wort

    • Extract standardized to 0.3% hypericin — only after checking your medications

Learn more about 5-HTP and St. John's Wort.