Purpose: To clarify the clinical role of topical glyceryl trinitrate (GTN) in the management of anal fissures.
Patients and methods: Fifty-six consecutive patients with fissure-in-ano attending a colorectal clinic from April 1997 to May 1998 included 16 acute and 40 chronic anal fissures. Patients were instructed to apply 0.2% 0.5 g of GTN to the painful area of the anus. Patients were followed-up in the clinic at 4, 8 and 12 weeks, and by telephone interviews at a median follow up of 10 months.
Results: Ten of 16 acute fissures (63%) were healed by 4 weeks and 13 (81%) by 8 weeks. Thirteen of 40 chronic fissures (33%) were healed by 8 weeks and 20 (50%) by 12 weeks. Seventeen patients (30%) underwent lateral sphincterotomy and all healed. There were five recurrences within 3 months of treatment with GTN. Thirty-four (61%) suffered from headaches, eight being severe headaches. None of the patients developed incontinence with GTN or lateral sphincterotomy.
Conclusions: Treatment of fissure-in-ano using GTN ointment was effective in up to 50% of patients with chronic anal fissure, and has the benefit of being repeatable if the fissure recurs. Patients should be aware that treatment is likely to take some months to be effective and is associated with significant side effects in up to 15% of patients.