Interaction studies have only been performed in adults.
Acyclovir, Ganciclovir and valacyclovir: Higher acyclovir plasma concentrations were observed when mycophenolate mofetil was administered with acyclovir in comparison to the administration of acyclovir alone. Because MPAG plasma concentrations are increased in the presence of renal impairment, as are acyclovir, ganciclovir and valaciclovir concentrations, the potential exists for these drug to compete for tubular secretion, and further increase in concentrations of these drugs may occur. Carefully monitor patients with renal impairment when these agents are coadministered.
Antacids with magnesium and aluminum hydroxides: Absorption of mycophenolate mofetil was decreased when administered with antacid.
Cholestyramine: Following coadministration of mycophenolate mofetil with cholestyramine, there was a 40% reduction in the AUC of MPA. Caution should be used during concomitant administration because of the potential to reduce efficacy of mycophenolate mofetil.
Medical products that interfere with enterohepatic recirculation: Caution should be used with medical products that interfere with enterohepatic recirculation because of the potential to reduce efficacy of mycophenolate mofetil.
Cyclosporin A: Coadministration of mycophenolate mofetil with cyclosporine A may reduce enterohepatic recirculation of mycophenolate. It is recommended to monitor mycophenolic acid concentrations and response to therapy. Adjust the mycophenolate dose as needed.
Rifampin: Concomitant use of rifampin with mycophenolate mofetil is resulted in a decrease in MPA exposure. It is recommended to monitor MPA exposure levels and to adjust mycophenolate mofetil doses accordingly to maintain clinical efficacy when rifampicin is administered concomitantly. Concomitant use of mycophenolate mofetil and rifampin is not recommended unless benefit outweighs risk.
Sevelamer: Decrease in MPA plasma concentrations were observed when mycophenolate mofetil was concomitantly administered with sevelamer. It is recommended to administer sevelamer 2 hours after intake mycophenolate mofetil.
Tacrolimus, Sirolimus: MPA trough plasma concentrations may be elevated, increasing the risk of adverse reactions. It is recommended to monitor plasma mycophenolate levels and adjust dose as needed.
Norfloxacin and metronidazole: Concomitant use of mycophenolate mofetil and the anti-infective combination of norfloxacin and metronidazole not recommended due to potential pharmacokinetic interaction (decreased systemic exposure of mycophenolic acid); however, no substantial effect on systemic exposure of mycophenolic acid was observed when mycophenolate mofetil was administered with norfloxacin or metronidazole.
Ciprofloxacin and amoxicillin plus clavulanic: Reductions in pre-dose (trough) MPA concentrations of about 50% have been reported in renal transplant recipients in the days immediately following commencement of oral ciprofloxacin or amoxicillin plus clavulanic acid. This effect tended to diminish with continued antibiotic use and to cease within a few days of their discontinuation. The change in pre-dose level may not accurately represent changes in overall MPA exposure. Therefore, a change in the dose of mycophenolate mofetil should not normally be necessary in the absence of clinical evidence of graft dysfunction. However, close clinical monitoring should be performed during the combination and shortly after antibiotic treatment.
Oral contraceptives: Potential pharmacokinetic interaction with concomitant use of levonogestrel with mycophenolate mofetil (decreased plasma concentrations of levonogestrel). Pharmacokinetic interaction unlikely with concomitant use of mycophenolate mofetil with ethinyl estradiol, desogestrel, or gestodene. Oral contraceptives should be administered with caution in patients receiving mycophenolate and additional methods of birth control methods should be used.
Live vaccines: Live vaccines should not be given to patients with an impaired immune response. The antibody response to other vaccines may be diminished.
Other interactions: Co-administration of probenecid with mycophenolate mofetil in animals raises plasma AUC of MPAG by 3-fold and MPA by 2-fold.