Supplement × Prescription·contraindicated·Strong evidence
St. John's Wort can markedly lower tacrolimus concentrations and cause rejection risk.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
What is happening. St. John's Wort can markedly lower tacrolimus concentrations and cause rejection risk.
Mechanism. CYP3A4 and P-glycoprotein induction reduces tacrolimus exposure.
Recommendation. Avoid completely unless the transplant team explicitly directs otherwise.
Effect on the composite score
If both St. John's Wort and Tacrolimus are in the same stack, this pair applies −25 to your Stack Score (per scored contraindication row).
The full algorithm, the clamping rules, and four worked stacks are at /methodology/stack-score.
Every claim on this page is cited. PMIDs link straight to PubMed.
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NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
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