Mycophenolate (CellCept or Myfortic) belongs to a class of medications known as immunosuppressives. This medication was used originally in the management of patients with organ transplants, but is now recommended in the treatment of some autoimmune diseases.
Mycophenolate has been used to treat people with lupus (especially those with symptoms of kidney disease), rheumatoid arthritis, vasculitis, inflammatory bowel disease such as Crohn’s disease, inflammatory eye disease (such as uveitis (iritis) and scleritis), and some other kidney or skin disorders.
How it works
Mycophenolate targets an enzyme in the body called inosine monophosphate dehydrogenase that is important for the formation of deoxyribonucleic acid (DNA) in cells. By interfering with DNA, the medication impairs function of immune system cells that become overactive in autoimmune diseases such as lupus.
In adults, mycophenolate typically is given twice daily for a total dose of 2 to 3 grams (2000 to 3000 mg) a day, although this dosage may be reduced in people with underlying kidney problems. The dose usually is lower than 2 grams a day for children.
Taking mycophenolate with food often helps to prevent side effects such as nausea or stomach pain. Mycophenolate comes in 250 mg and 500 mg capsules or tablets as well as in an intravenous form. People who prefer to take medication in liquid form can ask a pharmacist to prepare it as an oral suspension, but should not try to open the capsules or crush the tablets on their own.
Time to effect
Usually the first benefits of this medication are noticed in several weeks, but it may take several months or even longer to achieve maximum results.
The most common side effects with mycophenolate include upset stomach, nausea, vomiting or diarrhea. The frequency of these side effects may depend on the form of mycophenolate (e.g. mycophenolate mofetil (CellCept) or the delayed release mycophenolate sodium preparation, Myfortic). Other possible side effects include headache, dizziness, difficulty sleeping, tremor and, occasionally, rash. These side effects usually go away with time, but tell a doctor if they persist.
Less common but more serious side effects include a reduction of white blood cells (increasing the chances of infections, including viral infections such as herpes zoster (“shingles”), red blood cells that bring oxygen to tissues (which may lead to anemia), and platelets that aid clotting (which can lead to gastrointestinal bleeding). Periodic blood tests can detect reduced blood counts early on to avoid these problems.
Patients older than 65 may be at increased risk for some side effects, especially infections and gastrointestinal bleeding. People who have had ulcers or other serious gastrointestinal conditions should talk with their doctors before taking this medication.
Studies of transplant patients taking mycophenolate have found it may increase risk of some cancers such as lymphomas and skin cancers. Because there may be a similar risk in people with rheumatic conditions who take mycophenolate for long periods of time, discuss this issue with a physician before starting the medication. When on mycophenolate, it is important to see a physician regularly, use a sunscreen and avoid prolonged sun exposure.
Points to remember
Regular blood tests may be necessary for people taking mycophenolate. Such tests may be performed more frequently during the first several months, and then less often with time.
Notify your doctor if you bruise or bleed easily, or if you experience persistent or bloody diarrhea, shortness of breath, fevers or other signs of an infection.
The effects of mycophenolate during pregnancy have not been well studied, so it is not clear if mycophenolate causes birth defects. If you are pregnant or are considering having a child, you should discuss this with your doctor before beginning this medication. Use an effective form of birth control while taking this medication and for up to six weeks after you stop taking it. Because one study found that mycophenolate reduced the blood levels of some oral contraceptives (although it is not known if that meant it decreases their effectiveness), other forms of birth control are recommended. Do not breast-feed while taking mycophenolate because the drug may be passed into the breast milk.
Some vaccinations should be avoided while taking this medication. Be sure to discuss with your doctor before receiving any vaccines. You should discuss your vaccine history with your doctor as there may be reason to update some vaccines (such as pneumonia (Pneumovax), Hepatitis B, or the Herpes Zoster (Zostavax) vaccine in some cases) before starting this medication. Also, be sure to notify your doctor before any surgeries while taking this medication.
Tell your doctor about all of the medications you are taking, including over-the-counter drugs and natural remedies. A partial list of medications that may interfere with mycophenolate include:
- cholestyramine (Questran)
- acyclovir (Zovirax)
- gancyclovir (Cytovene)
- azathioprine (Imuran)
- antacids containing magnesium or aluminum hydroxide (such as Maalox, Rolaids, or Mylanta)
- oral contraceptives
- trimethoprim/sulfamethoxazole (Bactrim)
- theophylline (Theo-Dur)
- phenytoin (Dilantin)
- probenecid (Benemid)
- aspirin and other salicylates
Because many antacids interfere with the absorption of mycophenolate, they should not be taken at the same time. Instead, you should either take antacids at least 1 hour before mycophenolate or wait at least 2 hours after taking mycophenolate before taking an antacid.
Updated May 2012
Written by Michael Cannon, MD, and reviewed by the American College of Rheumatology Communications and Marketing Committee.
This patient fact sheet is provided for general education only. Individuals should consult a qualified health care provider for professional medical advice, diagnosis and treatment of a medical or health condition.
© 2012 American College of Rheumatology