Tolerability of aminosalicylates in inflammatory bowel disease

Since its synthesis in the 1930s and subsequent introduction, sulfasalazine has been an effective treatment for inflammatory bowel disease. However, u p to one-third of patients are unable to take the drug because of severe in tolerance. The finding in 1977 that the anticolitic effect of sulfasalazine lay in its 5-aminosalicylic [(5-ASA); mesalazine] moiety led to the develo pment of new generations of 5-ASA agents.