Methotrexate earlier known as amethopterin, is an antimetabolite and antifolate drug.
It is used in treatment of cancer, autoimmune diseases, ectopic pregnancy, and for the induction of medical abortions. It acts by inhibiting the metabolism of folic acid.
It is effective for the treatment of a number of cancers including: breast, head and neck, leukemia, lymphoma, lung, osteosarcoma, bladder, and trophoblastic neoplasms. It is used as a treatment for some autoimmune diseases including: rheumatoid arthritis, psoriasis, psoriatic arthritis, and Crohn's disease, to name a few. Although methotrexate was originally designed as a chemotherapy drug (in high doses), in low-doses methotrexate is a safe and well tolerated drug in the treatment of certain autoimmune diseases. Because of its efficacy and safety, low-dose methotrexate is now first-line therapy for the treatment of rheumatoid arthritis.
Methotrexate is available as Neotrexate Tablets which is packaged in 2.5 mg Tablets. Generic Methotrexate is also referred to as Neotrexate, Rheumatrex, Trexall, MTX, Amethopterin and Methotrexate.
The most common side effects of Methotrexate include ulcerative stomatitis, low white blood cell count and thus predisposition to infection, nausea, abdominal pain, fatigue, fever, dizziness and rarely pulmonary fibrosis.
Methotrexate is a highly teratogenic drug and categorized in pregnancy category X by the FDA. Women must not take the drug during pregnancy, if there is a risk of becoming pregnant, or if they are breastfeeding.
Men who are trying to get their partner pregnant must also not take Methotrexate . To engage in any of these activities (after discontinuing Neotrexate), women must wait until the end of a full ovulation cycle and men must wait three months.
To treat Choriocarcinoma and similar trophoblastic diseases the recommended Methotrexate is administered orally or intramuscularly in doses of 15 to 30 mg daily for a five-day course.
Such courses are usually repeated for 3 to 5 times as required, with rest periods of one or more weeks interposed between courses. Routine monitoring of the complete blood count, liver function tests, and creatine are recommended during Methotrexate therapy.
Penicillins may decrease the elimination of methotrexate and thus increase the risk of toxicity.
Additional Info: Prescribing Information
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