A rare drug reaction to methotrexate after treatment for ectopic pregnancy.

Abstract

Ectopic pregnancies are commonly diagnosed and treated in physicians' offices. In the hemodynamically stable patient, therapy often includes treatment with methotrexate. Well-known adverse effects of this drug include mucositis, abdominal cramping, and malaise. We report a case of a rare drug reaction after treatment with methotrexate. A 34-year-old, gravida 2, para 0, at 7 weeks of gestation by last menstrual period was diagnosed with an ectopic pregnancy and treated with methotrexate. The patient had an anaphylactoid reaction shortly after administration of methotrexate. Methotrexate is a commonly used therapy for ectopic pregnancies in the outpatient setting. Practitioners should be aware of the potential adverse reactions to methotrexate.