Quick Reference
- Scientific Rating
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2.9/ 5.0
- Primary Mechanism
- Crosses the blood-brain barrier and is converted to serotonin via aromatic L-amino acid decarboxylase, without the transport competition tryptophan fa
- Standardized Form
- Extracted from Griffonia simplicifolia seeds, typically standardized to 98-99% 5-HTP
5-Hydroxytryptophan (5-HTP) is synthesized in the body from the amino acid tryptophan and serves as the direct precursor to serotonin, a neurotransmitter involved in mood, appetite, and sleep regulation. Commercially, it is extracted from the seeds of the West African plant Griffonia simplicifolia rather than produced synthetically. Unlike tryptophan, 5-HTP does not compete with other amino acids for transport across the blood-brain barrier, which is the basis for its proposed advantage as a more direct route to raising brain serotonin availability. Clinical research has explored its use for mood support, sleep quality, and appetite regulation, though trial sizes remain modest and its most clinically significant consideration is its serotonergic interaction risk with common antidepressant medications.
Table of Contents
Clinical Summary
A recent randomized controlled trial in older adults found that 100 mg/day of 5-HTP over 12 weeks increased serum serotonin and modestly improved mood scores, though the trial was limited by a small sample size (n=30) and short duration. Earlier, smaller studies have explored dosing for depression, appetite regulation, and sleep, but the overall evidence base is considerably smaller than for more established serotonergic interventions.
Dosage Guidelines
50-300 mg/day, most commonly divided into two doses; clinical trials evaluating mood and cognition have most often used 100 mg/day.
Safety & Side Effects
Nausea and gastrointestinal upset are the most commonly reported effects, particularly when starting supplementation.
Known Interactions
Significant risk of serotonin syndrome when combined with SSRIs, SNRIs, MAOIs, tramadol, or triptans; concurrent use with any serotonergic medication should only occur under physician supervision.
Scientific References
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1
https://pubmed.ncbi.nlm.nih.gov/40944161/Source: pubmed.ncbi.nlm.nih.gov
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2
https://pubmed.ncbi.nlm.nih.gov/31504850/Source: pubmed.ncbi.nlm.nih.gov
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3
https://pubmed.ncbi.nlm.nih.gov/1384305/Source: pubmed.ncbi.nlm.nih.gov
Medical Disclaimer
The information provided in this clinical review is for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment.
*These statements have not been evaluated by the Food and Drug Administration (FDA). This product or ingredient is not intended to diagnose, treat, cure, or prevent any disease.
Always consult your physician or other qualified health provider with any questions you may have regarding a medical condition, or before beginning any new diet, fitness, supplement, or treatment regimen, especially if you have pre-existing medical conditions or are taking prescribed medications.