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

Supplement × Prescription·a caution·Emerging evidence

Berberine + Erythromycin

Q: Can I take Berberine and Erythromycin together?

Possibly, but with caution. Berberine and Erythromycin have a documented caution-tier interaction. Berberine inhibits CYP3A4 and P-glycoprotein. Erythromycin is itself a CYP3A4 substrate and inhibitor that can prolong the QT interval; adding berberine may raise erythromycin exposure and theoretically compound cardiac risk. Berberine also has its own QT-prolonging potential at higher doses.

Q: How does this affect a NutriStack Stack Score?

-5 to your Stack Score per scored caution row.

Caution Emerging evidence

Berberine inhibits CYP3A4 and P-glycoprotein. Erythromycin is itself a CYP3A4 substrate and inhibitor that can prolong the QT interval; adding berberine may raise erythromycin exposure and theoretically compound cardiac risk. Berberine also has its own QT-prolonging potential at higher doses.

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

Berberine and Erythromycin

Pair type

Caution

Evidence

Emerging

Source citations

Scope

Supplement × Prescription

Last verified

June 4, 2026

CautionEmerging evidence

What is happening. Berberine inhibits CYP3A4 and P-glycoprotein. Erythromycin is itself a CYP3A4 substrate and inhibitor that can prolong the QT interval; adding berberine may raise erythromycin exposure and theoretically compound cardiac risk. Berberine also has its own QT-prolonging potential at higher doses.

Mechanism. Berberine inhibition of CYP3A4 and P-gp can increase erythromycin plasma levels; potential additive effect on cardiac repolarization (QT interval).

Recommendation. Use caution and consider separating or avoiding berberine during a course of erythromycin, particularly in patients with cardiac risk factors, electrolyte abnormalities, or other QT-prolonging medications. Consult a prescriber before combining.

Stack Score

How it moves the number.

Effect on the composite score

If both Berberine and Erythromycin 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

1Guo Y, et al. Repeated administration of berberine inhibits cytochromes P450 in humans. European Journal of Clinical Pharmacology. 2012.Needs sourceNo link
2Owens RC, Nolin TD. Antimicrobial-associated QT interval prolongation. Clinical Infectious Diseases. 2006.Needs sourceNo link

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