Methotrexate injection is used alone or together with other medicines to treat several types of cancer such as breast, head and neck, lung, blood, bone, lymph node, and uterus cancers. Methotrexate is also used to treat adults with severe rheumatoid arthritis and children with polyarticular juvenile idiopathic arthritis who had other treatments that did not work well. It is also used to control symptoms of severe psoriasis in adults who have not been helped by other treatments.
Otrexup, generically known as methotrexate, belongs to a class of medication known as antimetabolites. Otrexup interferes with the growth of certain cells of the patient's body. This helps minimize the side effects of arthritis. It can also be used to treat severe psoriasis.