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Serotonin Precursor

5-HTP

Also known as: 5-Hydroxytryptophan

A compound that supports serotonin production, influencing mood, sleep, and emotional balance.

Evidence gradeCross-checked · Moderate-high
B+
WeakModerateStrong
4.0/ 5 rating

KÖGN Health grades 5-HTP as B+ (Moderate evidence) and rates it 4.0 out of 5.

Last reviewed · June 2026

CategoryNatural · Serotonin Precursor
Typical doseCommonly used at 50–300 mg/day, often started low and split, and sometimes taken in the evening for sleep. Enteric forms reduce nausea.
AvailabilityOTC

Primary effects

  • Improved mood
  • Better sleep
  • Stress reduction

How it works

Increases serotonin levels, supporting mood regulation and sleep quality.

Overview

5-HTP is a direct precursor to serotonin and is commonly used to support mood and sleep regulation. It can be effective for short-term mood support, but should be used cautiously due to its strong influence on serotonin pathways. It is often paired carefully with other compounds to avoid overstimulation of serotonin systems.

The evidence

5-HTP is a direct precursor to serotonin, so most of its evidence sits in mood and sleep rather than focus or memory. A Cochrane review found 5-HTP and tryptophan probably beat placebo for depressive symptoms, but flagged that few trials are of reliable quality and that proven, safer antidepressants exist. As a cognitive enhancer specifically, the evidence is thin.

How to dose it

Commonly used at 50–300 mg/day, often started low and split, and sometimes taken in the evening for sleep. Enteric forms reduce nausea.

When to take it

Both — some same-day calming, with mood effects building over weeks.

Safety & side effects

The most common effects are nausea and GI upset, which dose-splitting and enteric capsules reduce.

Who should avoid it

The key risk is serotonin syndrome: do not combine 5-HTP with antidepressants (SSRIs, SNRIs, MAOIs), triptans, tramadol or other serotonergic drugs without medical advice. Avoid in pregnancy. Because it bypasses normal regulation of serotonin synthesis, treat it more cautiously than its 'natural' label suggests.

References

Related ingredients

Graded entries that target the same cognitive goals.

Categories

Natural NootropicsMood & Emotional RegulationSleep & RecoverySerotonergics (Serotonin Support)Acute Performance NootropicsOver-the-Counter (OTC)Moderate-High Evidence

Draft — the dose, safety and evidence notes on this entry were prepared from the published literature and are pending editorial and clinical review.

Educational information, not medical advice. The evidence grade is KÖGN’s editorial assessment of published research, not a health claim. Speak to a qualified clinician before changing what you take.