5-HTP
Monograph · C5-Hydroxytryptophan
Direct precursor to serotonin. Crosses the blood-brain barrier and is decarboxylated to 5-HT (serotonin). Unlike tryptophan, bypasses the rate-limiting tryptophan hydroxylase step.
How it clearsHalf cleared in ~5h. Most (~96%) gone by ~1d.
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This compound sits in research-grey territory. The caveats below carry more weight than for FDA-approved entries — read them.
Evidence: depression (comparable to SSRIs in small trials, but NOT a replacement), fibromyalgia pain (emerging), and appetite suppression. Not to be combined with SSRIs or SNRIs (serotonin syndrome risk). In peptide stacks, 5-HTP is used for mood stabilization and sleep quality. Timing: take 30–60 min before sleep for serotonin → melatonin conversion benefit. Long-term use may deplete dopamine precursors — often stacked with L-DOPA or tyrosine to balance.
Promising cognitive signal that holds up in early trials — but cognitive effects resist self-assessment at low deltas. The brain adjusts to its own baseline quickly, meaning real improvements can feel like nothing from the inside. Task performance tracks better than sensation here.
CONTRAINDICATED with SSRIs, MAOIs, SNRIs, tramadol — serotonin syndrome risk. GI upset at higher doses. Long-term use without dopamine precursor balance may worsen mood over time. Eosinophilia-myalgia syndrome (EMS) risk is low with reputable 5-HTP sources but verify sourcing.
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- CLimited evidence
Direct precursor to serotonin
1 supporting referencesVerified 24d ago
External links to PubMed searches, ClinicalTrials.gov, and FDA materials. We do not host papers — we point at canonical sources.
Dietary supplement (DSHEA). Not FDA-approved as a drug. The 1989 EMS outbreak was linked to a contaminated tryptophan batch (not 5-HTP itself) but drove regulatory scrutiny.
Distilled themes from named communities — Reddit threads, forums, creator commentary. Not direct quotes; not clinical evidence. Useful for calibrating expectations against what real self-experimenters report.
Used in sleep stack with melatonin + magnesium. Most users report mood improvement at 100 mg but flag nausea at higher doses. Users on SSRIs universally warned not to combine.
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