What kind of interaction is it?

Contraindicated: the two should not be combined; the risk outweighs any benefit.

Is this interaction backed by published research?

Yes. NutriStack lists 2 citation rows for the Fluvoxamine + L-Tryptophan pair, each linking to PubMed by PMID where available. Full sourcing methodology at https://nutristackapp.com/methodology/interactions.

Interaction databaseSupplement × PrescriptionReviewed May 2026

Fluvoxamine and L-Tryptophan, contraindicated.

Q: Can I take Fluvoxamine and L-Tryptophan together?

No. Fluvoxamine and L-Tryptophan are contraindicated together. L-Tryptophan is the upstream precursor to serotonin; combined with fluvoxamine's serotonin reuptake blockade, it can drive synaptic serotonin to toxic levels and trigger serotonin syndrome (tremor, sweating, agitation, hyperthermia, clonus). This mirrors the well-documented SSRI plus tryptophan contraindication.

Q: How does this affect a NutriStack Stack Score?

-25 to your Stack Score per scored contraindication row.

L-Tryptophan is the upstream precursor to serotonin; combined with fluvoxamine's serotonin reuptake blockade, it can drive synaptic serotonin to toxic levels and trigger serotonin syndrome (tremor, sweating, agitation, hyperthermia, clonus). This mirrors the well-documented SSRI plus tryptophan contraindication.

2 primary source citations. Strong evidence. Last verified May 30, 2026.

Open the interaction checker →Read the methodology

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.

Sourcing standards·Evidence tiers

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: Fluvoxamine and L-Tryptophan
Pair type: Contraindicated
Evidence (highest tier): Strong
Source citations: 2 sources
Stack Score effect: −25 to your Stack Score (per scored contraindication row).
Scope: Supplement × Prescription
Last verified: May 30, 2026

Contraindicated · Strong evidence

Contraindicated

What is happening. L-Tryptophan is the upstream precursor to serotonin; combined with fluvoxamine's serotonin reuptake blockade, it can drive synaptic serotonin to toxic levels and trigger serotonin syndrome (tremor, sweating, agitation, hyperthermia, clonus). This mirrors the well-documented SSRI plus tryptophan contraindication.

Mechanism. L-Tryptophan is converted to 5-HTP by tryptophan hydroxylase, then to serotonin. Fluvoxamine blocks SERT, preventing reuptake. Combined, both synthesis and clearance are pushed, raising synaptic 5-HT to toxic levels.

Recommendation. Do not take L-tryptophan supplements with fluvoxamine. Food intake of tryptophan is fine; the problem is concentrated supplemental doses.

Sources (2)

Stack Score

How this pair moves the number.

Effect on the composite score

If both Fluvoxamine and L-Tryptophan are in the same stack, this pair applies −25 to your Stack Score (per scored contraindication row).

The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.

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