Isosorbide dinitrate in the treatment of anal fissure: a randomised, prospective, double blind, placebo-controlled trial.

OBJECTIVE

To assess the efficacy of isosorbide dinitrate in healing anal fissures.

DESIGN

Randomised, prospective, double blind, placebo controlled trial.

SETTING

Teaching hospital, The Netherlands.

SUBJECTS: 37 consecutive subjects with anal fissure diagnosed in the surgical outpatient department.

INTERVENTIONS: After randomisation, 20 patients were given isosorbide dinitrate, and 17 patients placebo.

MAIN OUTCOME MEASURES: Healing of anal fissure, recurrence, and tolerance.

RESULTS

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).

CONCLUSIONS

Isosorbide dinitrate is an effective treatment for anal fissure, and is significantly better than placebo.