Joseph A. Govert, MD; Suzanne Patton, MD, PhD; Robert L. Fine, MD
To the Editors: Methotrexate is currently used for the treatment of psoriasis, asthma, rheumatoid arthritis, and cancer. Hazardous interactions may occur when combined with other drugs whose mechanism of action involves the same biochemical pathway. One such rarely described interaction is between low-dose, oral methotrexate and the antibiotic trimethoprim-sulfamethoxazole (TMP-SMX) resulting in marrow hypoplasia (1-3).
A 58-year-old, white man with a long history of rheumatoid arthritis presented with symptoms and signs of prostatitis. His arthritis had been successfully managed with oral methotrexate, 7.5 mg weekly since 1988. A complete blood count showed a hemoglobin of 133 g/L, a hematocrit of
Joseph A. Govert, Suzanne Patton, Robert L. Fine. Pancytopenia from Using Trimethoprim and Methotrexate. Ann Intern Med. 1992;117:877–878. doi: 10.7326/0003-4819-117-10-877_2
Download citation file:
Published: Ann Intern Med. 1992;117(10):877-878.
Copyright © 2017 American College of Physicians. All Rights Reserved.
Print ISSN: 0003-4819 | Online ISSN: 1539-3704
Conditions of Use