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Underrecognized postdosing reactions to methotrexate in patients with rheumatoid arthritis
1Division of Rheumatology, University of South Alabama College of Medicine, Mobile.
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.
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