Olsalazine is an anti-inflammatory drug used in the treatment of Inflammatory Bowel Disease and Ulcerative Colitis. It is sold under the name Dipentum.

The chemical name is 3,3' -azobis (6-hydroxybenzoate)salicylic acid. It is sold as the disodium salt.

Like Balsalazide, Olsalazine is believed to deliver Mesalazine, or 5-aminosalicylic acid (5-ASA), past the small intestine, directly to the large intestine, which is that active site of disease in ulcerative colitis.