GENERIC NAME: azathioprine
BRAND NAME: Imuran, Azasan
DRUG CLASS AND MECHANISM: Azathioprine is an immunosuppressant, that is, a drug that is used to suppress the immune system. It is used to treat patients who have undergone kidney transplantation and for diseases in which modifying the activity of the immune system is important. Azathioprine is a prodrug (a precursor of a drug) which is converted in the body to its active form called mercaptopurine (Purinethol). The exact mechanism of action of azathioprine is not known.
Like other immunosuppressants, it suppresses the proliferation of T and B lymphocytes, types of white blood cells that are part of the immune system and defend the body against both infectious diseases and foreign materials. For example, in the case of organ transplantation, immunosuppressants prevent the body from immunologically rejecting the new organ. In the case of autoimmune diseases (diseases caused by an abnormal immune reaction against the body's own tissues) such as rheumatoid arthritis, suppressing the immune system reduces the inflammation that accompanies immune reactions and slows damage to the joints caused by the inflammation. The FDA approved azathioprine in March 1968.
GENERIC AVAILABLE: Yes
PREPARATIONS: Tablet: 25, 50, 75, 100 mg. Injection: 100 mg
STORAGE: Azathioprine should be stored at 15 C -25 C (59 F -77 F) in a dry place and protected from light.
PRESCRIBED FOR: Azathioprine is used for preventing rejection of transplanted kidneys. Azathioprine also is used for the treatment of active rheumatoid arthritis.
Non-FDA approved uses for azathioprine include multiple sclerosis, where several clinical trials have shown decreases in relapses but no slowing in progression of the disease. There also is limited data on the safety of azathioprine in multiple sclerosis. Other non-FDA (off-label) uses of azathioprine include Crohn's disease, myasthenia gravis, chronic ulcerative colitis, and autoimmune hepatitis (in combination with prednisone).
Quick GuideRheumatoid Arthritis (RA) Pictures Slideshow
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