Methotrexate-induced Neutropenia

Various malignancies, autoimmune disorders such as rheumatoid arthritis (RA), and elective abortions commonly use methotrexate (MTX) for their treatment, which is a folate antagonist. Although many cases of the common side effects of MTX such as nausea, vomiting, and stomatitis have been reported, very few cases of MTX-induced neutropenia have been found in the literature. We have taken a case of neutropenia that developed after the patient took tablet MTX for RA. The case was studied and the causality assessment of the reported adverse drug reaction showed it to be in the category of "probable" according to the WHO-UMC causality categories.