NutriStack
L-Tryptophan and Sertraline, a caution.
L-Tryptophan is the dietary amino acid precursor to serotonin. Supplemental tryptophan increases serotonin synthesis, and combined with sertraline's reuptake inhibition, can cause excessive serotonergic activity. Cases of serotonin syndrome have been reported with this combination.
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
- L-Tryptophan and Sertraline
- Pair type
- Caution
- Evidence (highest tier)
- Moderate
- Source citations
- 1 source
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Moderate evidence
Caution
What is happening. L-Tryptophan is the dietary amino acid precursor to serotonin. Supplemental tryptophan increases serotonin synthesis, and combined with sertraline's reuptake inhibition, can cause excessive serotonergic activity. Cases of serotonin syndrome have been reported with this combination.
Mechanism. L-Tryptophan is hydroxylated by tryptophan hydroxylase to 5-HTP, then decarboxylated to serotonin. Supplemental tryptophan increases substrate availability for serotonin synthesis. Sertraline's SERT inhibition prevents the clearing of this excess serotonin from synapses.
Recommendation. Avoid supplemental L-tryptophan while taking sertraline. Dietary tryptophan from food is generally safe. If already taking both, discontinue L-tryptophan and inform your prescriber.
Stack Score
How this pair moves the number.
Effect on the composite score
If both L-Tryptophan and Sertraline 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.
Check your full routine
One pair was the worked example. NutriStack runs every pair in your stack at once.
Drop in your supplements and prescriptions and the public database surfaces every interaction, synergy, timing rule, and contraindication, every one linked to its primary source.