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 Passionflower + Valerian Root pair, each linking to PubMed by PMID where available. Full sourcing methodology at https://nutristackapp.com/methodology/interactions.

Interaction databaseSupplement × SupplementReviewed May 2026

Passionflower and Valerian Root, a caution.

Q: Can I take Passionflower and Valerian Root together?

Possibly, but with caution. Passionflower and Valerian Root have a documented caution-tier interaction. Both herbs are sedative and GABAergic, so combining them produces additive drowsiness and CNS depression, an effect used in some combination sleep products but a concern with driving or other sedatives.

Q: How does this affect a NutriStack Stack Score?

-5 to your Stack Score per scored caution row.

Both herbs are sedative and GABAergic, so combining them produces additive drowsiness and CNS depression, an effect used in some combination sleep products but a concern with driving or other sedatives.

2 primary source citations. Moderate 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: Passionflower and Valerian Root
Pair type: Caution
Evidence (highest tier): Moderate
Source citations: 2 sources
Stack Score effect: −5 to your Stack Score (per scored caution row).
Scope: Supplement × Supplement
Last verified: May 30, 2026

Caution · Moderate evidence

Caution

What is happening. Both herbs are sedative and GABAergic, so combining them produces additive drowsiness and CNS depression, an effect used in some combination sleep products but a concern with driving or other sedatives.

Mechanism. Passionflower flavonoids and valerian constituents both enhance GABA-A receptor signaling, producing additive inhibitory CNS effects.

Recommendation. If combined, start low, avoid driving or operating machinery, and do not add other sedatives or alcohol. Discuss with a clinician if taking prescription CNS depressants.

Sources (2)

Stack Score

How this pair moves the number.

Effect on the composite score

If both Passionflower and Valerian Root 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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