Home/Ingredients/5-HTP (Griffonia Seed)

5-HTP (Griffonia Seed)

Mood · sleep · serotonin precursor

Moderate evidenceVegan114 studies on PubMedRead the research
Written to our editorial standards · reviewed against published research· Updated 30 May 2026
Last reviewed: May 30, 2026

5-HTP: Mood · sleep · serotonin precursor. Direct precursor to serotonin and melatonin. May support mood and sleep onset, use cautiously, not with SSRIs. Standard dose 100 mg, taken in the evening, about $14/month. Evidence rating: moderate evidence.

Where to buy

NOW Foods 5-HTP 100mg
Recommended
NOW Foods, 5-HTP
100 mg · Evening · ~$14/month

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NOW Foods 5-HTP 100mgBestseller
5-HTP 100mg
NOW Foods
120 veg capsules · $16 · ★ 4.7
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Nutricost 5-HTP 100 mgBest Value
5-HTP 100 mg
Nutricost
120 caps · $16 · ★ 4.5
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Swanson 5-HTP 100 mgPremium
5-HTP 100 mg
Swanson
120 caps · $14 · ★ 4.5
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NOW Foods 5-HTP 100 mgBest Value
5-HTP 100 mg
NOW Foods
120 veg caps · $20 · ★ 4.7
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Doctor's Best 5-HTP 100 mgPremium
5-HTP 100 mg
Doctor's Best
120 veg caps · $18 · ★ 4.7
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What is 5-HTP?

5-Hydroxytryptophan (5-HTP) is the immediate precursor to serotonin, the neurotransmitter that regulates mood, appetite, and the sleep-wake cycle. Derived from the West African Griffonia simplicifolia seed, it crosses the blood-brain barrier and is converted into serotonin without requiring tryptophan competition. Clinical research has explored 5-HTP for low mood, sleep onset difficulties, and appetite regulation. Doses typically range from 50-200 mg in the evening. 5-HTP should never be combined with SSRIs, MAOIs, or other serotonergic medications without medical supervision, due to the risk of serotonin syndrome. Cycling rather than continuous use is advised.

Direct precursor to serotonin and melatonin. May support mood and sleep onset, use cautiously, not with SSRIs.

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Common questions

What is 5-HTP?
5-Hydroxytryptophan (5-HTP) is the immediate precursor to serotonin, the neurotransmitter that regulates mood, appetite, and the sleep-wake cycle. Derived from the West African Griffonia simplicifolia seed, it crosses the blood-brain barrier and is converted into serotonin without requiring tryptophan competition. Clinical research has explored 5-HTP for low mood, sleep onset difficulties, and appetite regulation. Doses typically range from 50-200 mg in the evening. 5-HTP should never be combined with SSRIs, MAOIs, or other serotonergic medications without medical supervision, due to the risk of serotonin syndrome. Cycling rather than continuous use is advised.
What is 5-HTP used for?
Mood · sleep · serotonin precursor. Direct precursor to serotonin and melatonin. May support mood and sleep onset, use cautiously, not with SSRIs.
What is the standard dose of 5-HTP?
100 mg, typically taken in the evening. Approximate cost is $14 per month.
Who should avoid 5-HTP?
Use extra caution, and speak to a clinician first, if you are pregnant or nursing, taking SSRIs/MAOIs, bipolar disorder.
How strong is the evidence for 5-HTP?
Moderate evidence for its primary uses. See the full study list on the research page.

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