Methotrexate (also called MTX for short) is a medication prescribed for rheumatoid arthritis (RA). Methotrexate is a disease-modifying antirheumatic drug (DMARD), which means it slows the progression of RA. It’s the most commonly prescribed DMARD for RA, perhaps because it’s recommended by leading medical associations (such as the American College of Rheumatology and the European League Against Rheumatism) as a first treatment. Methotrexate can be used at any stage of the disease, on its own in the early stages or in combination with other medications. Methotrexate is also used to treat psoriasis, psoriatic arthritis, juvenile arthritis, lupus, and some forms of cancer (at much higher doses than for RA).
No one knows exactly how methotrexate works, but it interferes with processes in the body that cause inflammation and joint damage. So it relieves the joint pain, swelling, redness, and fatigue that come with RA.
Methotrexate comes in two forms for RA—an oral pill and a subcutaneous shot. Most people start out taking the pill form, but they may switch to subcutaneous methotrexate if the pills don’t work as well as they once did. Taking methotrexate subcutaneously helps get more of the drug into a person’s system. You may want to ask your doctor about the different dosing options and which one is right for you.
Methotrexate has a long history of safety and is considered one of the safest treatments for RA. That doesn’t mean it doesn’t have any side effects, however. Gastrointestinal symptoms (stomach upset and vomiting) can occur with oral methotrexate.