Learn more about methotrexate, a commonly mtx arthritis drug used to treat rheumatoid arthritis and certain other rheumatic conditions. Methotrexate was approved by the FDA in 1988 for the treatment of rheumatoid arthritis.
Prior to its approval for rheumatoid arthritis, methotrexate had been used to treat psoriasis and cancer. It was originally developed as a leukemia drug in the 1940s. The drug is used to reduce pain and swelling associated with rheumatoid arthritis, prevent joint damage, and lower the risk of disability by slowing disease progression. Improvement from methotrexate may be seen as soon as three to six weeks, but it may require 12 weeks or possibly even up to six months of treatment for full benefit to be realized. Methotrexate interferes with certain enzymes which play a role in immune system function. By doing so, it affects the production of a form of folic acid which is needed for actively growing cells.
It remains unclear exactly how methotrexate decreases arthritis activity. Oral methotrexate is taken one day a week for rheumatoid arthritis. It is not taken daily like most pills. Methotrexate is available in 2.
The starting dose for most adults with rheumatoid arthritis is 7. If needed, the total dose of methotrexate can be increased to 20 or 25 milligrams each week. The brand name Rheumatrex dose pack contains blister cards containing the exact number of pills to take each week. The brand name Trexall is available in 5, 7.
5, 10, and 15-milligram tablets. Methotrexate can cause abnormal liver function. It’s important to routinely have your blood tested for liver function so your doctor can monitor you for unwanted side effects. Other than abnormalities with liver function, the most common side effects associated with methotrexate are nausea and vomiting. The side effects already mentioned—nausea, vomiting, and liver function—may be dose-dependent. If you have any of these side effects, adjusting the dose may eliminate the problem.
Many people experience no significant side effects while taking methotrexate. Ideally, you should not drink alcohol if you take methotrexate. At most, with your doctor’s permission, you should have no more than two drinks per month. Methotrexate should not be taken by people with known chronic liver or kidney disease. A rheumatologist may decide to prescribe methotrexate to people with mild liver or mild kidney disease—but with vigilance and an abundance of caution.
Methotrexate may need to be stopped prior to a surgical procedure, temporarily, while you are healing. This is due to a possible effect on the immune system and potential increased risk of infection with its use. Anyone treated with methotrexate should take a folic acid supplement. Methotrexate should not be taken if you are pregnant or plan to become pregnant. Methotrexate can cause serious birth defects as well as pregnancy complications. You should be using some form of contraception while taking methotrexate and for three months after you stop taking methotrexate.