OBJECTIVE: To report previously underrecognized postdosing side effects of methotrexate (MTX).METHODS: Over a one and a half year period, in 2 practices, all patients with rheumatoid arthritis (RA) receiving weekly MTX, and volunteering symptoms within a few hours of MTX dosing were carefully questioned concerning the nature of the postdosing reaction.RESULTS: Of 356 patients, 36 (10%) reported a previously underemphasized postdosing reaction consisting of arthralgias/myalgias, fatigue/malaise or both. Sixteen patients discontinued MTX primarily because of this side effect.CONCLUSION: In these patient populations, postdosing reactions were the 2nd most common side effect (after gastrointestinal) leading to MTX withdrawal.
Administration, Oral Arthralgia