NutriStack
5-HTP and Rizatriptan, a caution.
5-HTP is a serotonin precursor, and rizatriptan is a 5-HT1B/1D receptor agonist. Direct case evidence for this exact pair is limited, but the combination is pharmacologically avoidable because both increase serotonergic signaling. Symptoms of concern include agitation, tremor, sweating, diarrhea, clonus, fever, or confusion.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- 5-HTP and Rizatriptan
- Pair type
- Caution
- Evidence (highest tier)
- Emerging
- Source citations
- 3 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Emerging evidence
Caution
What is happening. 5-HTP is a serotonin precursor, and rizatriptan is a 5-HT1B/1D receptor agonist. Direct case evidence for this exact pair is limited, but the combination is pharmacologically avoidable because both increase serotonergic signaling. Symptoms of concern include agitation, tremor, sweating, diarrhea, clonus, fever, or confusion.
Mechanism. 5-HTP increases serotonin synthesis after decarboxylation to serotonin. Rizatriptan activates serotonin 5-HT1B/1D receptors; this can add to serotonergic tone and contribute to serotonin receptor overstimulation in susceptible patients.
Recommendation. Avoid 5-HTP supplements while using rizatriptan unless your prescriber specifically approves. If you have taken both and develop tremor, fever, marked restlessness, muscle jerks, or confusion, seek urgent care. Do not rely on dose spacing to remove the risk.
Sources (3)
- Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Altern Med Rev. 1998;3(4):271-280. PMID 9727088
- Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005;352(11):1112-1120. PMID 15784664
- Evans RW, Tepper SJ, Shapiro RE, Sun-Edelstein C, Tietjen GE. The FDA alert on serotonin syndrome with use of triptans combined with selective serotonin reuptake inhibitors or selective serotonin-norepinephrine reuptake inhibitors: American Headache Society position paper. Headache. 2010;50(6):1089-1099. PMID 20618823
Stack Score
How this pair moves the number.
Effect on the composite score
If both 5-HTP and Rizatriptan are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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