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an antimetaboliteantineoplastic agent that inhibits the conversion of folic acid to tetrahydrofolic acid by binding the enzyme dihydrofolate reductase, thus inhibiting DNA synthesis; it is specific for the S phase of the cell cycle. Used as the base and the sodium salt in the treatment of leukemias, lymphomas, sarcomas, and cancer of the head and neck, breast, colon, lung, testes, and other organs. Called also MTX. It is also used in the treatment of psoriasis and rheumatoid arthritis. Administered orally, intravenously, intramuscularly, intrathecally, or intra-arterially.


Methotrexate, see there.

Patient discussion about MTX

Q. Is methotrexate available in the United States as a treatment for fibromyalgia? Last year I was diagnosed as fibromyalgia. I feel a lot of fatigue and stiffness. I came upon a website from where I read that rheumatoid arthritis causes those same symptoms and can be treated with methotrexate. After reading that, I purchased a half year supply of the drug over the counter in Mexico. It eliminated all of my symptoms. A month after my supply ran out, all the symptoms returned. Is methotrexate available in the United States as a treatment for fibromyalgia?

A. Yes fatigue and stiffness are some of the symptoms of fibromyalgia. Methotrexate is certainly available in the United States, but it is not approved for nor used as a treatment for fibromyalgia. It was originally developed to treat cancer and subsequently found to be very effective for a number of inflammatory disorders, such as RA and psoriasis. Because fibromyalgia is not an inflammatory disorder – that is, there is no identifiable inflammation in the muscles or joints in individuals with this condition – it is not clear why you responded to this drug. You should tell your physician about your response to methotrexate. It may be possible that you have an inflammatory disorder rather than – or in addition to – fibromyalgia.

More discussions about MTX
References in periodicals archive ?
Amongst the 12 patients whose treatment on MTX+ LEF combination was discontinued; 4 patients had diarrhea, 2 patients had severe oral ulcers, 2 had markedly raised ALT, 1 had severe vomiting, 1 patient developed abscess, 1 developed MTX Induced pneumonitis and another one had a severe chest infection.
After MTX infusion for 0, 24, 48, and 72 h, contralateral venous blood (2 ml) was taken.
In 3 of our 4 patients, the serum [beta]-hCG levels initially increased after the first systemic MTX treatment but after the complementary medical treatment, they showed a steady decline.
13 used MTX dose in the range of 15-20mg/week according to the severity of disease while we used a standard dose of 15mg/week irrespective of severity or type of the disease which may explain the reason of higher percentage of non-efficacy of the drug in our study.
MTX is a possible risk factor for insufficiency fractures in patients with rheumatoid arthritis, although a causal link between methotrexate and insufficiency fractures is debatable.
Forty-two patients that received YF vaccination during treatment with MTX were described.
MTX is a widely used anti-cancer drug and a well-known immunosuppressant introduced for therapeutic application in 1950 (11).
The most common problem encountered with MTX is the development of resistance to tumors.
This, paired with a very good tolerability and safety profile, has since made MTX the anchor drug for the treatment of RA.