Sulfasalazine: A rare cause of acute eosinophilic pneumonia

Sulfasalazine is a compound of 5-aminosalicylic acid (5-ASA) and sulfapyridine joined by an azo bond. It is a widely used drug in the treatment of chronic inflammatory bowel disease. Fatal toxicity of sulfasalazine arises from its effects on the bone marrow and the resulting blood dyscrasias. Pulmonary toxicity from sulfasalazine is a rather rare finding. Here, we present the case of a patient who developed acute eosinophilic pneumonia with sulfasalazine use.