OBJECT DRUGS

• Mycophenolate (CellCept, etc.)

PRECIPITANT DRUGS

Binding Agents:

• Antacids
• Calcium Polycarbophil (FiberCon, Konsyl)
• Cholestyramine (Questran, etc.)
• Colestipol (Colestid)
• Iron
• Sevelamer (Renagel, etc.)
• Sucralfate (Carafate)

Comment:

Cholestyramine can substantially reduce mycophenolate mofetil (MM) serum concentrations by binding in the gastrointestinal tract and interfering with its enterohepatic circulation. Colestipol theoretically would have a similar effect. Aluminum-magnesium antacids modestly reduce MM absorption. The effect of iron on MM may be less in patients taking cyclosporine plus MM.

Class 3: Assess Risk & Take Action if Necessary

• Circumvent/Minimize: Since the interaction appears to be due to interruption of MM enterohepatic circulation, separation of doses is not likely to circumvent the interaction completely. Nonetheless, if the combination is used, separate the doses as much as possible and monitor for reduced MM effect.
• Consider Alternative:
• Lipid Lowering Agents: The use of alternative hypolipidemic such as HMG-CoA reductase inhibitors should be considered. The effect of colesevelam (Welchol) on MM is not established, but it might interact.
• Antacids: Antisecretory agents such as H₂-receptor antagonists or proton pump inhibitors would be less likely to interact than antacids.
• Monitor: Patients receiving mycophenolate with binding resins or antacids should be monitored for reduced immunosuppressant efficacy.