Topical 0.2% glyceryl trinitrate ointment for anal fissures: long-term efficacy in routine clinical practice

OBJECTIVE: Randomized controlled trials have reported fissure healing rates of 60-70% using topical 0.2% GTN ointment, but the effectiveness of this therapy in routine clinical practice, particularly in the long term, is uncertain. This study aimed to evaluate the efficacy of topical GTN for anal fissures in an outpatient setting. PATIENTS AND METHODS: A case note review and postal questionnaire survey were undertaken for patients with a diagnosis of anal fissure dispensed 0.2% GTN ointment from one hospital pharmacy over a two year period (June 1996-May 1998). RESULTS: Ninety-three patients (53 male) applied 0.2% GTN ointment twice daily to the anoderm for anal fissure. They were reviewed on average 8 (2-16), weeks later, by which time 57 (61%) fissures had healed, 33 persisted and 3 patients were lost to follow up. Seventy-two patients (41male), median age 42 (22-83) years, returned completed questionnaires (77% response rate). Forty-nine (68%) had healed with GTN, but 25 had recurrent symptoms after a median of 6 (1-18) months. Sixteen of those patients reporting symptomatic recurrence were prescribed further GTN for a recurrent fissure: 14 (88%) healed, but 2 persisted, and had surgery. In the other nine patients symptoms resolved spontaneously. Thirty-five (49%) experienced headaches, 3 (4%) discontinuing treatment as a result. The median follow up was 25 (13-36) months. CONCLUSION: 0.2% GTN heals 60% of fissures in the outpatient setting but half the patients develop headaches. Up to one third of healed fissures may recur within 18 months but the majority respond to further GTN. Only 4% of patients initially healed with GTN later require sphincterotomy for recurrences.