Does Ketoconazole Interact With Tacrolimus?

Use this combination with caution. Your prescriber may monitor you more closely or adjust doses.

Interactions like this one can happen when two medicines have overlapping effects, or when one changes how the other is absorbed, broken down, or cleared from the body. Ketoconazole is a azole antifungal (strong cyp3a4 inhibitor) and Tacrolimus is a calcineurin inhibitor immunosuppressant; together they are documented as a moderate interaction. How much this matters depends on your dose, your other medications, and your overall health.

If you have been prescribed both Ketoconazole and Tacrolimus, do not start, stop, or change either medication on your own — some medicines are unsafe to stop suddenly. Tell your prescriber and pharmacist that you take both so they can decide whether the combination is right for you, adjust the dose, monitor you more closely, or suggest an alternative.

Strong CYP3A Inhibitors : Protease inhibitors (e.g., nelfinavir, telaprevir, boceprevir, ritonavir), azole antifungals (e.g., voriconazole, posaconazole, itraconazole, ketoconazole), antibiotics (e.g., clarithromycin, troleandomycin, chloramphenicol), nefazodone, letermovir, Schisandra sphenanthera extracts May increase tacrolimus whole blood trough concentrations and increase the risk of serious adverse reactions (e.g., neurotoxicity, QT prolongation).

Source: FDA structured product labeling (set_id 08cf2861-2483-405d-a872-a88a5c235f9a).