Drug Interaction Report

ADJUST DOSING INTERVAL: Coadministration with antacids may decrease the oral bioavailability of mycophenolic acid. The exact mechanism of interaction is unknown but may involve chelation with polyvalent ions in antacids or enhanced drug solubility induced by an increase in gastric pH, or both. The interaction has been reported with magnesium/aluminum-containing antacids.

MANAGEMENT: Patients treated with oral mycophenolic acid who require an antacid or antacid-containing preparation (e.g., didanosine buffered tablets or pediatric oral solution) should separate the administration times of the medications by at least two hours.

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.