Diltiazem and Tacrolimus interaction
Diltiazem and Tacrolimus: the Tacrolimus prescribing label describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Tacrolimus (ASTAGRAF XL) label · effective 2026-01-14
• Hypertension: May require antihypertensive therapy; monitor relevant drug interactions.
The risk for nephrotoxicity may increase when ASTAGRAF XL is concomitantly administered with CYP3A inhibitors (by increasing tacrolimus whole blood concentrations) or drugs associated with nephrotoxicity (e.g., aminoglycosides, ganciclovir, amphotericin B, cisplatin, nucleotide reverse transcriptase inhibitors, protease inhibitors).
Some antihypertensive drugs can increase the risk for hyperkalemia [see Warnings and Precautions ( 5.8 )] .
Calcium-channel blocking agents may increase tacrolimus blood concentrations and require dosage reduction of ASTAGRAF XL [see Drug Interactions ( 7.2 )] .
Risk of Rejection with Strong CYP3A Inducers and Risk of Serious Adverse Reactions with Strong CYP3A Inhibitors The concomitant use of strong CYP3A inducers may increase the metabolism of tacrolimus, leading to lower whole blood trough concentrations and greater risk of rejection.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
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.