Mycophenolate Mofetil

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Mycophenolate Mofetil MMF (brand name CellCept) is an immuno-suppressant drug used for the treatment of autoimmune conditions such as AIHA, some types of cancer and as an anti-rejection drug for human organ transplant recipients. Mycophenolate Mofetil can take much longer than prednisone to suppress the immune system so treatment response may not be seen immediately.

Dosage: 10 to 20 mg per kg bid, 12 hours apart. MMF can have serious drug interactions, for example with azathioprine. Follow your vet’s instructions. Stomach protection medications should be given 2 hours before or 2 hours after MMF, otherwise they can interfere with absorption.

Side effects: There are not many studies of MMF treatment in dogs with AIHA available. MMF can cause diarrhea, vomiting, lack of appetite and gastrointestinal bleeding. One study reported that MMF treatment was discontinued because all dogs suffered from suspected MMF induced gastointestinal toxicity (severe diarrhea, vomiting, anorexia, gastro-intestinal bleeding. Lowering the dose may reduce the side effects. MMF may suppress the bone marrow which could lead to anemia and reduced white blood cell populations. This would increase the risk of infections. Liver enzymes may become elevated. With long term use there are increased risks for cancers and bone marrow suppression.

Decrease dosage gradually when the dog has reached a stable condition.

Dogs treated with this drug should not be bred because it can alter DNA in rapid growth cells.

MMF can have serious interactions with other drugs. Advise your vet about any other medicines or supplements being given.

Vaccinations should not be administered during treatment with MMF.

There are few studies of MMF treatment in dogs. Side effects seen in humans may also be seen in dogs. Gastrointestinal side effects, stomach and intestinal rupture, blood in urine, high blood pressure, fluid retention, breathing and lung problems (fluid in lungs) , cough, chest pain, infection, shaking, itching, decreased WBC count, dose related leukopenia, anemia, thrombocytopenia and neutropenia. Pure red cell aplasia (PRCA) has been reported in MMF patients treated in combination with additional immuno-suppressive drugs.

Other side effects include blurred vision, head pain, dizziness, urinary tract infection, rapid heart rate, pancreatitis, malignant lymphoma. Kidney side effects include urinary tract infections, blood in the urine and kidney tubular necrosis.