Skin rash, fever and rigors caused by olsalazine

Objective: To report a case where a patient receiving olsalazine for control of ulcerative colitis developed high fever with rigors and a skin rash. Patient: A 61 -year-old man with ulcerative colitis who was known to be intolerant to sulphasalazine. Results: Symptoms resolved rapidly following withdrawal of olsalazine. The patient was discharged and on follow-up 3 months later reported no further fever, rigors or malaise. Conclusions: The rapid improvement in symptoms following cessation of therapy with olsalazine is suggestive of hypersensitivity to either 5-aminosalicylic acid or its acetylated form. This case reinforces the need to be cautious when 5-aminosalicylic acid is used in patients known to be intolerant to sulphasalazine