5-aminosalicylic acid (5-ASA),, also known as mesalamine or Mesalazine is a medication used to treat inflammatory bowel disease, including ulcerative colitis and Crohn's disease.
5-Aminosalicylic acid is a monohydroxybenzoic acid that is salicylic acid substituted by an amino group at the 5-position. It has a role as a non-steroidal anti-inflammatory drug. It is an aromatic amine, an amino acid, a member of phenols, a monocarboxylic acid and a monohydroxybenzoic acid. It derives from a salicylic acid.