Methotrexate is used to treat leukemia and certain types of cancer of the breast, bones, skin, head and neck, or lung.
Methotrexate is also used to treat severe psoriasis and rheumatoid arthritis in adults, and to treat active polyarticular-course juvenile rheumatoid arthritis in children.
Methotrexate is often used when other medicines have not been effective.
Methotrexate may also be used for purposes not listed in this medication guide.