Drug Interaction Report

ADJUST DOSING INTERVAL: Consumption of food has led to a 27% decrease in the bioavailability of orally administered tacrolimus.

MANAGEMENT: Tacrolimus should be administered at least one hour before or two hours after meals.

GENERALLY AVOID: Grapefruit juice has been reported to increase tacrolimus trough concentrations. Data are limited, but inhibition of the CYP450 enzyme system appears to be involved.

MANAGEMENT: The clinician may want to recommend that the patient avoid ingesting large amounts of grapefruit juice while taking tacrolimus.

ADJUST DOSING INTERVAL: Administration of enteric coated mycophenolic acid with meals may alter its pharmacokinetics relative to administration in the fasting state. When mycophenolic acid 720 mg was administered with a high-fat meal, there was a 33% decrease in the peak plasma concentration (Cmax); a 3.5-hour increase in delay time for the rise of plasma mycophenolic acid; and a 5-hour delay in the time to reach peak plasma concentration (Tmax). However, no effect was observed on the systemic exposure of mycophenolic acid.

MANAGEMENT: To avoid variability in drug absorption between doses, enteric coated formulations of mycophenolic acid should be taken on an empty stomach, one hour before or two hours after food intake. The tablets should be swallowed whole and not crushed, chewed or divided in order to maintain the integrity of the enteric coating.