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 Sertraline + St. John's Wort pair, each linking to PubMed by PMID where available. Full sourcing methodology at https://nutristackapp.com/methodology/interactions.

Interaction databaseSupplement × PrescriptionReviewed May 2026

Sertraline and St. John's Wort, contraindicated.

Q: Can I take Sertraline and St. John's Wort together?

No. Sertraline and St. John's Wort are contraindicated together. Combining sertraline (an SSRI) with St. John's Wort creates a serious risk of serotonin syndrome, a potentially life-threatening condition. St. John's Wort inhibits serotonin reuptake and may also inhibit MAO, dramatically increasing synaptic serotonin when combined with an SSRI.

Q: How does this affect a NutriStack Stack Score?

-25 to your Stack Score per scored contraindication row.

Combining sertraline (an SSRI) with St. John's Wort creates a serious risk of serotonin syndrome, a potentially life-threatening condition. St. John's Wort inhibits serotonin reuptake and may also inhibit MAO, dramatically increasing synaptic serotonin when combined with an SSRI.

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: Sertraline and St. John's Wort
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. Combining sertraline (an SSRI) with St. John's Wort creates a serious risk of serotonin syndrome, a potentially life-threatening condition. St. John's Wort inhibits serotonin reuptake and may also inhibit MAO, dramatically increasing synaptic serotonin when combined with an SSRI.

Mechanism. Sertraline blocks the serotonin transporter (SERT), increasing synaptic serotonin. St. John's Wort also inhibits serotonin reuptake (via hyperforin) and may inhibit monoamine oxidase. The combined serotonergic effects can cause excessive serotonin accumulation at postsynaptic 5-HT receptors, triggering serotonin syndrome.

Recommendation. Do not take St. John's Wort with sertraline or any SSRI. This is a well-documented dangerous interaction with risk of serotonin syndrome (symptoms include agitation, confusion, rapid heart rate, high blood pressure, dilated pupils, muscle twitching, and hyperthermia).

Sources (2)

Stack Score

How this pair moves the number.

Effect on the composite score

If both Sertraline and St. John's Wort 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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