Which oral aminosalicylate for ulcerative colitis?

People with ulcerative colitis, an idiopathic inflammatory bowel disease affecting the colorectum, are traditionally treated with aminosalicylates (all of which contain the active compound 5-aminosalicylic acid [5-ASA]). There are now over 10 oral aminosalicylate preparations available in the UK for ulcerative colitis. Drug treatment for the condition is usually started in secondary care and continued by the patient's GP. Here we explore the types of oral aminosalicylates available and whether any one preparation offers significant advantage over another.