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

Supplement × Prescription·a caution·Moderate evidence

Nebivolol + St. John's Wort

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

Possibly, but with caution. Nebivolol and St. John's Wort have a documented caution-tier interaction. St. John's Wort is a broad inducer of drug-metabolizing enzymes. While nebivolol is primarily a CYP2D6 substrate, St. John's Wort can reduce the plasma concentrations and antihypertensive efficacy of many cardiovascular drugs through enzyme and transporter induction, potentially undermining blood-pressure control.

Q: How does this affect a NutriStack Stack Score?

-5 to your Stack Score per scored caution row.

Caution Moderate evidence

St. John's Wort is a broad inducer of drug-metabolizing enzymes. While nebivolol is primarily a CYP2D6 substrate, St. John's Wort can reduce the plasma concentrations and antihypertensive efficacy of many cardiovascular drugs through enzyme and transporter induction, potentially undermining blood-pressure control.

Supplement × Prescription

Open the interaction checker → Read the methodology

From the database

What the row says.

Every entry follows the same shape: what is happening, the mechanism, and the recommendation.

Substances

Nebivolol and St. John's Wort

Pair type

Caution

Evidence

Moderate

Source citations

Scope

Supplement × Prescription

Last verified

June 4, 2026

CautionModerate evidence

What is happening. St. John's Wort is a broad inducer of drug-metabolizing enzymes. While nebivolol is primarily a CYP2D6 substrate, St. John's Wort can reduce the plasma concentrations and antihypertensive efficacy of many cardiovascular drugs through enzyme and transporter induction, potentially undermining blood-pressure control.

Mechanism. St. John's Wort (hyperforin) induces cytochrome P450 enzymes and P-glycoprotein, which can increase clearance of cardiovascular drugs and lower their plasma levels and therapeutic effect.

Recommendation. Avoid combining St. John's Wort with nebivolol where possible. If already taken together, monitor blood pressure closely; loss of control may require dose adjustment. Do not stop St. John's Wort abruptly without considering rebound changes in any co-administered medications. Consult the prescriber.

Stack Score

How it moves the number.

Effect on the composite score

If both Nebivolol and St. John's Wort 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 at /methodology/stack-score.

Sources

Sources, by evidence tier.

Every claim on this page is cited. PMIDs link straight to PubMed.

Reference material

1Borrelli F, Izzo AA. Herb-drug interactions with St John's wort (Hypericum perforatum): an update on clinical observations. AAPS J. 2009.Needs sourceNo link
2Nicolussi S, Drewe J, Butterweck V, Meyer zu Schwabedissen HE. Clinical relevance of St. John's wort drug interactions revisited. Br J Pharmacol. 2020.Needs sourceNo link

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