Methotrexate is one of the immunosuppressant, cytoxic drugs used for the treatment of Lupus. It is often used in conjunction with Prednisone (or other corticosteroids) so that you can keep your dosage of Prednisone low (it is also called a "steroid-sparing" drug). Low dosages of Methotrexate (Rheumatrex), such as 7.5 mg given orally once per week, are extremely effective in the treatment of lupus, especially when used with low dosages of Prednisone.
Another commonly used steroid-sparing drug is Imuran. Now, Both medications have been around for a long time. Methotrexate is most often used for rheumatoid arthritis and arthritic-like pain in Lupus, while Imuran was used extensively in patients with kidney transplants but is now found to be effective in patients with Lupus. Both are generally well tolerated and their side effects are similar. Both drugs can affect the liver and blood counts and must be monitored with regular bloodwork.
Lupus (systemic lupus erythematosus, or SLE) is an autoimmune disease, in which the immune system attacks the body's own tissues as though they were foreign substances. Immunosuppressive medications, including cytotoxics, reduce inflammation and suppress the immune system. The dosage of Methotrexate that is used for Lupus is much lower than the dosage used to treat certain forms of cancer. Because its dosage is much lower, the side-effects are not as toxic. We cannot tell you what you should do, but hopefully, if you have a better understanding of why the medication is used, you may be able to make an informed decision.
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