St. John's wort and Tacrolimus interaction
St. John's wort and Tacrolimus: the Tacrolimus prescribing label flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
Curated guidance for St. John's wort
St. John's wort can weaken these medicines by speeding up their breakdown, which can mean organ rejection, clots, or loss of effect.
From the Tacrolimus (ASTAGRAF XL) label · effective 2026-01-14
Strong CYP3A Inducers c : Antimycobacterials (e.g., rifampin, rifabutin), anticonvulsants (e.g., phenytoin, carbamazepine and phenobarbital), St John’s wort May decrease tacrolimus whole blood trough concentrations and increase the risk of rejection [see Warnings and Precautions ( 5.10 )].
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.