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 1 citation row for the Luteolin + St. John's Wort pair, each linking to PubMed by PMID where available. Full sourcing methodology at https://nutristackapp.com/methodology/interactions.

Supplement × Supplement·a caution·Emerging evidence

Luteolin + St. John's Wort

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

Possibly, but with caution. Luteolin and St. John's Wort have a documented caution-tier interaction. Luteolin inhibits several cytochrome P450 enzymes (including CYP3A4 and CYP1A2) and drug transporters, whereas St. John's Wort is a potent inducer of CYP3A4 and P-glycoprotein. Co-use creates opposing and unpredictable effects on the metabolism of many medications.

Q: How does this affect a NutriStack Stack Score?

-5 to your Stack Score per scored caution row.

Caution Emerging evidence

Luteolin inhibits several cytochrome P450 enzymes (including CYP3A4 and CYP1A2) and drug transporters, whereas St. John's Wort is a potent inducer of CYP3A4 and P-glycoprotein. Co-use creates opposing and unpredictable effects on the metabolism of many medications.

Supplement × Supplement

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

Luteolin and St. John's Wort

Pair type

Caution

Evidence

Emerging

Source citations

Scope

Supplement × Supplement

Last verified

June 4, 2026

CautionEmerging evidence

What is happening. Luteolin inhibits several cytochrome P450 enzymes (including CYP3A4 and CYP1A2) and drug transporters, whereas St. John's Wort is a potent inducer of CYP3A4 and P-glycoprotein. Co-use creates opposing and unpredictable effects on the metabolism of many medications.

Mechanism. Luteolin is a CYP inhibitor; St. John's Wort is a CYP3A4/P-gp inducer, producing conflicting modulation of hepatic drug clearance.

Recommendation. Avoid relying on this combination to manage any medication regimen. Anyone on St. John's Wort for mood should consult a clinician before adding luteolin, since St. John's Wort itself has extensive drug interactions.

Stack Score

How it moves the number.

Effect on the composite score

If both Luteolin 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

1Si D, et al. Mechanism of CYP2C9 inhibition by flavones and flavonols. Drug Metabolism and Disposition. 2009.Needs sourceNo link

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