Last reviewed 2026-04-23 · How we verify

5-hidroxitriptophan

5-hydroxytryptophan (5-HTP) is a precursor to serotonin that increases central nervous system serotonin levels by crossing the blood-brain barrier and being converted to serotonin via aromatic amino acid decarboxylase.

5-hydroxytryptophan (5-HTP) is a precursor to serotonin that increases central nervous system serotonin levels by crossing the blood-brain barrier and being converted to serotonin via aromatic amino acid decarboxylase. Used for Depression, Anxiety disorders, Fibromyalgia.

At a glance

Mechanism of action

5-HTP is an amino acid intermediate in the serotonin synthesis pathway. It is more effective than L-tryptophan at raising brain serotonin because it bypasses the rate-limiting step of tryptophan hydroxylase and crosses the blood-brain barrier more efficiently. Increased serotonin availability can improve mood, reduce pain perception, and normalize sleep-wake cycles.

Approved indications

• Depression
• Anxiety disorders
• Fibromyalgia
• Sleep disorders

Common side effects

• Nausea
• Gastrointestinal upset
• Headache
• Dizziness
• Serotonin syndrome (rare, with concurrent serotonergic agents)

Key clinical trials

• Proof-of-concept Study to Evaluate the Safety and Efficacy of Tryptophan in Patients with BPH. (PHASE2)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• 5-hidroxitriptophan CI brief — competitive landscape report
• 5-hidroxitriptophan updates RSS · CI watch RSS
• Clinical Academic Center (2CA-Braga) portfolio CI