Nitroglycerin ointment for anal fissures: effective treatment or just a headache?

Topical nitrates have been shown to cause nitric oxide-mediated relaxation of the internal anal sphincter. Previous reports have suggested initial efficacy in the treatment of anal fissures. The aim of this study was to assess the longer-term usefulness of this treatment.

Thirty-three patients with an anal fissure were treated with topical 0.3% nitroglycerin ointment, applied to the anoderm three times per day and after bowel movements. Patients were followed up by office visits and telephone calls until symptoms were completely resolved or treatment was noted to be ineffective or intolerable.

Thirty-three patients were treated, 16 with acute fissures, and 17 with chronic fissures. Nitroglycerin was effective in 9 of 16 acute fissures (56%), and 7 of 17 chronic fissures (41%). Even when effective, 75% of patients reported an adverse reaction.

Topical nitroglycerin was only effective in approximately one-half of patients with an anal fissure. There was a very high incidence of adverse reactions. In our experience nitroglycerin more often causes a headache than treats the symptoms of anal fissure.