Induced Allergic Hemolysis

Crossover studies have shown that mesalazine has about a 10-fold lower potential than sulfasalazine for inducing allergic reactions or causing intolerance. Adverse effects with all aminosalicylates include (generally more frequent with sulfasalazine) headache, nausea, abdominal pain, dyspepsia, fatigue, rash, fever, rarely exacerbation of the disease, pancreatitis, pericarditis, pneumonitis, liver disease, nephritis, and bone marrow depression. Watery diarrhea is an adverse effect unique to olsalazine, while anorexia, folate malabsorption, hemolysis, neutropenia, agranulocytosis, male infertility, and neuropathy are unique to sulfasalazine. 

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