What kind of interaction is it?

Caution: an interaction that may reduce efficacy or raise side-effect risk and warrants monitoring.

Is this interaction backed by published research?

Yes. NutriStack lists 2 citation rows for the St. John's Wort + Suvorexant pair, each linking to PubMed by PMID where available. Full sourcing methodology at https://nutristackapp.com/methodology/interactions.

Interaction databaseSupplement × PrescriptionReviewed May 2026

St. John's Wort and Suvorexant, a caution.

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

Possibly, but with caution. St. John's Wort and Suvorexant have a documented caution-tier interaction. Suvorexant exposure is sensitive to CYP3A modulation, and St. John's Wort can induce CYP3A4. Combining them may lower suvorexant levels and reduce sleep benefit; stopping St. John's Wort can then restore exposure and increase next-day sleepiness. The effect depends on the hyperforin content of the St. John's Wort product.

Q: How does this affect a NutriStack Stack Score?

-5 to your Stack Score per scored caution row.

Suvorexant exposure is sensitive to CYP3A modulation, and St. John's Wort can induce CYP3A4. Combining them may lower suvorexant levels and reduce sleep benefit; stopping St. John's Wort can then restore exposure and increase next-day sleepiness. The effect depends on the hyperforin content of the St. John's Wort product.

2 primary source citations. Emerging 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: St. John's Wort and Suvorexant
Pair type: Caution
Evidence (highest tier): Emerging
Source citations: 2 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. Suvorexant exposure is sensitive to CYP3A modulation, and St. John's Wort can induce CYP3A4. Combining them may lower suvorexant levels and reduce sleep benefit; stopping St. John's Wort can then restore exposure and increase next-day sleepiness. The effect depends on the hyperforin content of the St. John's Wort product.

Mechanism. St. John's Wort induces CYP3A4 via hyperforin-mediated pregnane X receptor activation. Suvorexant is primarily metabolized by CYP3A, so induction can reduce systemic exposure and hypnotic effect.

Recommendation. Avoid St. John's Wort while using suvorexant unless your prescriber approves. Do not raise suvorexant to overcome reduced effect from the herb. If St. John's Wort is stopped, monitor for stronger sedation and next-day impairment.

Sources (2)

Stack Score

How this pair moves the number.

Effect on the composite score

If both St. John's Wort and Suvorexant 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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