Isosorbide Dinitrate in the Treatment of Anal Fissure: A Randomised, Prospective, Double Blind, Placebo-controlled Trial

Abstract

To assess the efficacy of isosorbide dinitrate in healing anal fissures. Randomised, prospective, double blind, placebo controlled trial. Teaching hospital, The Netherlands. 37 consecutive subjects with anal fissure diagnosed in the surgical outpatient department. After randomisation, 20 patients were given isosorbide dinitrate, and 17 patients placebo. Healing of anal fissure, recurrence, and tolerance. Both groups were treated for a median (range) of 5 weeks (range 1-10). After this period, 17 in the isosorbide group had healed compared with 6 controls (p < 0.003). The fissure recurred in 2 patients who had had an initial good response to isosorbide, and in 2 in the control group. Side effects (particularly headache) were more common after isosorbide dinitrate, but not significantly so (9/20 compared with 3/17). Isosorbide dinitrate is an effective treatment for anal fissure, and is significantly better than placebo.