Methotrexate for Rheumatoid Arthritis

Methotrexate is administered once weekly as a single dose or in divided doses given over a 24-hour period. To reduce the incidence of major toxic effects, methotrexate should never be given in daily doses. Relative contraindications include renal dysfunction, liver disease, active infectious disease and excessive alcohol consumption. Both women and men of reproductive age should use birth control during methotrexate therapy. Potential drug interactions include salicylates and nonsteroidal anti-inflammatory drugs, which are both commonly used in patients with rheumatoid arthritis or psoriasis. A premethotrexate evaluation is important to ensure proper patient selection for this effective but potentially toxic drug. (am fam physician 2000;62:1607-12,1614.