Methotrexate is indicated in the treatment of gestational choriocarcinoma, chorioadenoma destruens, and hydatidiform mole. In acute lymphocytic leukemia, methotrexate is indicated in the prophylaxis of meningeal leukemia and is used in maintenance therapy in combination with other chemotherapeutic agents. methotrexate tablets, usp warnings methotrexate should be used only by physicians whose knowledge and experience include the use of antimetabolite therapy because of the possibility of Methotrexate is a drug that is used to treat childhood acute lymphocytic leukemia, lymphoma, and cancers of the lung, head, neck, and breast as well as rheumatoid arthritis and psoriasis. Methotrexate is an antimetabolite of the antifolate type. It is thought to affect cancer and rheumatoid arthritis by two different pathways. For cancer, methotrexate competitively inhibits dihydrofolate reductase (DHFR), an enzyme that participates in the tetrahydrofolate synthesis. Ejima-Yamada K, Oshiro Y, Okamura S, et al. Epstein-Barr virus infection and gene promoter hypermethylation in rheumatoid arthritis patients with methotrexate-associated B cell lymphoproliferative disorders. This site uses cookies. By continuing to browse this site you are agreeing to our use of cookies. Methotrexate is a medicine available in a number of countries worldwide. A list of US medications equivalent to Methotrexate is available on the Drugs.com website. Methotrexate was first introduced in 1955 for leukemia and in 1986 became FDA approved for the treatment of adults with severe, active, rheumatoid arthritis or children with active polyarticular-course juvenile RA. Methotrexate reference guide for safe and effective use from the American Society of Health-System Pharmacists (AHFS DI). Medline ® Abstract for Reference 78 of 'Therapeutic use and toxicity of high-dose methotrexate'.