From the databaseWhat the row says.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
Scope
Supplement × Prescription
Last verified
June 4, 2026
CautionEmerging evidence
What is happening. Berberine may alter CYP3A or P-glycoprotein activity and make tacrolimus concentrations unpredictable.
Mechanism. Potential transporter and enzyme modulation.
Recommendation. Avoid unsupervised berberine; check trough levels if exposure changes are possible.
Stack Score
How it moves the number.
Effect on the composite score
If both Berberine and Tacrolimus 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.
SourcesSources, by evidence tier.
Every claim on this page is cited. PMIDs link straight to PubMed.
Reference material
1- 1U.S. National Library of Medicine. Tacrolimus Capsules US Prescribing Information. 2026.Needs sourceNo link