5-Hydroxytryptophan · Griffonia simplicifolia
5-HTP (5-Hydroxytryptophan) is the direct serotonin precursor, derived from L-tryptophan by tryptophan hydroxylase. Unlike L-tryptophan, 5-HTP does not require this rate-limiting enzyme and is converted to serotonin via aromatic amino acid decarboxylase. This makes 5-HTP a more direct serotonin booster than L-tryptophan supplementation.
Evening for sleep; morning for mood. Do NOT combine with SSRIs.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
5-HTP bypasses the rate-limiting tryptophan hydroxylase step:
AADC (aromatic amino acid decarboxylase) converts 5-HTP → serotonin. Both peripheral and CNS conversion occur.
Serotonin → N-acetyl-serotonin → melatonin (via pineal gland). Indirect sleep support.
AADC requires vitamin B6 (PLP). Some products include B6 to support conversion.
Without carbidopa, much 5-HTP is converted peripherally to serotonin (which doesn't cross BBB). Carbidopa-co-administered 5-HTP enters CNS more efficiently. Most supplement use is without carbidopa - effects rely on small CNS fraction.
Combined with SSRIs, MAOIs, tramadol, MDMA, or other serotonergic drugs - serotonin excess can produce agitation, hyperthermia, autonomic instability, and rarely death. Single most important interaction.
Days 1-7: subtle effects.
Weeks 2-6: peak mood effect.
Cycle off after 12 weeks.
Each reference below was re-fetched from its PubMed record, and the quoted sentence was confirmed to appear in that abstract and to support the claim it sits under. Follow any of them to read the source.
Primary safety concern: serotonin syndrome is a recognized safety issue reviewed for 5-HTP.
Safety issues with 5-HTP are also reviewed, with emphasis on eosinophilia myalgia syndrome (EMS) and serotonin syndrome.
Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophan.
Evidence scope. Narrative review spanning preclinical and human evidence; general safety topic, no specific dose or route.
Dose/route boundary: 100 mg oral 5-HTP twice daily was tested; the abstract reports no benefit for IBD-related fatigue.
Patients were treated in a crossover manner with 100 mg oral 5-hydroxytryptophan or placebo twice daily for 2 consecutive periods of 8 weeks.
Evidence scope. Human, IBD patients in remission but fatigued (disease-specific); oral, 100 mg twice daily, 8-week crossover periods.
Dose/route: 100 mg oral 5-HTP daily was used in older adults, within the card’s 50-100 mg 1-3x/day range.
Thirty older adults (66 ± 3 years) in Singapore were randomly assigned to either consume or not consume 100 mg 5-HTP daily.
Evidence scope. Human, healthy older adults in Singapore (n=30), not disease-specific; oral supplement, 100 mg once daily, 12 weeks.
Oral mechanism/route: orally administered 5-HTP is systemically absorbed.
5-HTP is well absorbed from an oral dose, with about 70 percent ending up in the bloodstream.
5-Hydroxytryptophan: a clinically-effective serotonin precursor.
Evidence scope. Narrative review (1998) of general oral pharmacokinetics; not population- or condition-specific.
Plasma
Post-ingestion
Hours plasma; cumulative neurotransmitter effects over weeks
Oral ~70%
Daily dosing for sustained effects
AADC conversion + hepatic
Storage. Capsule. Cool dry location.
Dietary supplement (US, DSHEA). Banned in some EU jurisdictions.
Put it to work
Open 5-HTP straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open 5-HTP in the app →Go deeper
The complete 5-HTP walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
Join the community ↗Track it in OnePin. Log vials, draws, and protocols in the app.
Type a name, brand, or tool. Esc closes.