Effect of isosorbide dinitrate ointment on anal fissure

Until recently, the treatment of choice for anal fissure was surgery, consisting of a partial lateral internal sphincterotomy. This treatment has a high complication rate: impaired continence is reported in 8-30% of the patients in the literature. Therefore, recently nonsurgical treatment modalities have been developed, such as local application of isosorbide dinitrate (ISDN) ointment. This treatment has comparable effectiveness with lower complication rates. To study the effect of ISDN on the healing of anal fissures in a general surgical practice, a prospective study was performed in our hospital.

In the period between June 1997 and January 2000, 100 consecutive patients with anal fissure were treated with ISDN.

Of these 100 patients, 93 were healed within 8 weeks and 7 patients had no response and were operated. Of the 93 patients with primary healing fissures, 13 patients had recurrence during the 1-year follow-up. Seven of them were cured with ISDN, and the remaining 6 patients needed surgery. The only complication observed in this study was temporary headache which was observed in 7 patients.

The primary healing rate of anal fissures was 93% with ISDN. In case of recurrence, 54% (7/13) could again be treated successfully with ISDN. Therefore, we recommend ISDN as first choice treatment for primary and recurrent anal fissures.