Underrecognized postdosing reactions to methotrexate in patients with rheumatoid arthritis.
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.


CONCLUSIONS
In these patient populations, postdosing reactions were the 2nd most common side effect (after gastrointestinal) leading to MTX withdrawal.
Halla
J T
JT
Division of Rheumatology, University of South Alabama College of Medicine, Mobile.
Hardin
J G
JG
D000284:Administration, Oral; D018771:Arthralgia / Q000139:chemically induced; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005221:Fatigue / Q000139:chemically induced; D005260:Female; D006801:Humans; D007263:Infusions, Parenteral; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged; D009135:Muscular Diseases / Q000139:chemically induced; D010146:Pain / Q000139:chemically induced; D013997:Time Factors
D008727:Methotrexate