5-HTP

Category: amino-acid

Aliases: 5-hydroxytryptophan

Pharmacological Mechanism

Direct serotonin precursor (see serotonin melatonin axis); bypasses tryptophan hydroxylase.

Half-Life (t½)

PO: 2h

Dosing Guidelines

• PO: Typical 100 (Range: 50–300)

Target Organ Systems

• nervous

Interactions

• Tryptophan (synergistic): Upstream; 5-HTP bypasses rate-limiting tryptophan hydroxylase.
• Vitamin B6 (synergistic): AADC cofactor.
• Serotonin (synergistic): Immediate serotonin precursor — the practical supplement route.

Notes

Do not combine with SSRIs/MAOIs.

Pathways It Modulates

• Kynurenine pathway (inhibitor) — shunts Trp pool toward 5-HT branch (away from KP)
• Tryptophan → serotonin → melatonin (substrate) — AADC step

Chemical Identifiers

• PubChem CID: 144
• Formula: C11H12N2O3
• Molecular weight: 220.22 g/mol
• InChIKey: LDCYZAJDBXYCGN-UHFFFAOYSA-N
• SMILES: C1=CC2=C(C=C1O)C(=CN2)CC(C(=O)O)N

References

• PMID 9727088
• PMID 18308795