A 38-year-old man presented with a generalized pruritic maculopapular rash, fever, myalgias, and edema of the face and neck. Laboratory examination revealed eosinophilia, atypical lymphocytosis, and abnormal liver function results. The clinical course was characterized by rapid resolution after initiation of steroid therapy and withdrawal of sulfasalazine, which had been started three weeks earlier for abdominal cramping and diarrhea. This clinical picture suggests a drug-induced hypersensitivity reaction to a drug commonly used for inflammatory bowel disease, sulfasalazine.