Azulfidine® (sulfasalazine) is a prescription medication used to treat mild-to-moderately active cases of ulcerative colitis. Although it is officially approved to treat ulcerative colitis only, Azulfidine also has some "off-label" uses (or indications). These off-label (or unapproved) uses of Azulfidine include treating Crohn's disease and rheumatoid arthritis.
Azulfidine comes in tablet form and is thought to work by slowing down the production of certain inflammatory cells in the lining of the colon. It is approved for use in adults and children as young as six years old. However, there is also a delayed-release tablet formulation of this medication (Azulfidine EN-tabs), which is approved for the treatment of rheumatoid arthritis.
(To learn more about the indications for this drug, click Azulfidine Uses. This article also explains in more detail how Azulfidine works and lists some of the other treatment options for ulcerative colitis.)