5-hydroxytryptophan
5-HTP
What it is5-hydroxytryptophan, the immediate precursor of serotonin, bypassing the rate-limiting hydroxylase.
Why it mattersIt raises serotonin without needing tryptophan hydroxylase, which is why it is sold as an antidepressant supplement.
What it changes⚑ Serotonin syndrome with SSRIs and MAOIs; peripheral conversion causes nausea unless carbidopa is co-given.
FDA-approved for
- dietary supplement (serotonin precursor; no approved indication)
Off-label
- depression (weak evidence)
- insomnia
- fibromyalgia
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Not stated on label | Adults and children ≥12 yr | 5 drops PO QD | 5–10 drops PO QD | 10 drops PO QD |
| Not stated on label | Children <12 yr | Consult physician before use | Consult physician before use | Undefined |
Renal Undefined
Hepatic Undefined
Instructions
- Oral liquid; take drops by mouth.
- Discontinue and consult a health care professional if symptoms persist >7 days.
- Consult a physician before use in children <12 yr.
Available strengths
- cap 50, 100, 200 mg
Pregnancy Undefined
Lactation Undefined
Cost
5-hydroxytryptophan (5-HTP)
| Strength | #/mo | generic $/mo | CostPlus | |
|---|---|---|---|---|
| 50 mg | cap | 30 qd | not offered | |
| 100 mg | cap | 30 qd | not offered | |
| 200 mg | cap | 30 qd | not offered |
NADAC is a voluntary CMS survey of what retail community pharmacies pay for the drugs they stock. 5-hydroxytryptophan is dispensed outside retail pharmacies, so it rarely appears on surveyed invoices.
NO BOXED WARNINGS
Principal riskSerotonin syndrome with SSRIs and MAOIs