Foam preparations for the treatment of ulcerative colitis

Patients with ulcerative colitis uniformly have disease involving the distal colon. When patients have disease limited to the left colon or symptoms suggestive of active rectal inflammation, guidelines recommend topical rectal therapies as first-line agents either as monotherapy or in conjunction with oral products. Rectal delivery modalities offer the advantage of delivering high local concentrations of active medication to the site of maximal inflammation with minimization of systemic side effects. Methods of rectal administration include suppositories, liquid enemas and foams. Suppositories are limited to the treatment of rectal disease, and patients often have difficulty retaining the liquid enema secondary to its high volume and consistency. Rectal foams reliability extend to the descending and sigmoid colon with application. Foams are further characterized by increased viscosity, lower volumes, finer dispersion on the colonic mucosa, and increased adhesiveness to the colonic mucosa compared with liquid enemas. Additionally, rectal foam agents demonstrate equal efficacy to their liquid enema counterparts yet consistently yield better patient tolerance, lower incidence of side effects, and increased patient acceptability. Currently available agents include 5-aminosalicylic acid and corticosteroids, both first and newer generation. This review focuses on clinical trials assessing efficacy, tolerability, and patient preferences for these agents as well as describing the currently available rectal foam products.