A randomized trial of oral vs. topical diltiazem for chronic anal fissures

Chemical sphincterotomy has proved effective in treating chronic anal fissure. Glyceryl trinitrate is the most widely used agent, and topical 0.2 percent glyceryl trinitrate ointment heals up to two thirds of chronic anal fissures. Unfortunately, however, many patients experience troublesome headaches as a side effect of this treatment. This study assessed the effectiveness of oral and topical diltiazem in healing chronic fissures.

Fifty consecutive patients with chronic anal fissures were randomly assigned to receive oral (60 mg) or topical (2 percent gel) diltiazem twice daily for up to eight weeks. Anal manometry was performed before and after the first dose, and blood pressure was recorded at 15-minute intervals. Patients were reviewed fortnightly, pain was expressed with a visual linear analog scale, blood pressure was recorded, fissure healing was assessed, and side effects were noted.

Twenty-four patients received oral diltiazem, and 26 received topical diltiazem. Mean (+/- standard error of the mean) maximum resting anal pressures fell by 15 and 23 percent from 95 +/- 4 to 81 +/- 4 and from 102 +/- 5 to 79 +/- 5 cm H2O in the two groups, respectively. There was no significant reduction in blood pressure during the study or at follow-up in either group. Fissure healing was complete in 9 patients (38 percent) receiving oral diltiazem and 15 (65 percent) on topical treatment by eight weeks. Oral diltiazem caused side effects in eight patients (rash, two; headaches, two; nausea or vomiting, three; reduced smell and taste, one), whereas no side effects were seen in those receiving topical therapy (P = 0.001).

Oral and topical diltiazem heal chronic anal fissures. Topical diltiazem is more effective, achieving healing rates comparable to those reported with topical nitrates, with significantly fewer side effects.