Background:0.2 per cent topical glyceryl trinitrate (GTN) ointment heals up to two-thirds of chronic anal fissures in adults although many patients experience troublesome headaches. This double blind randomised pilot study assessed the efficacy and side effects of 0.1 and 0.05 per cent GTN ointment in treatment of chronic anal fissures in children.Material/Methods:15 consecutive children with chronic anal fissures were randomised to receive either 0.05 or 0.1 per cent GTN ointment applied topically twice daily for eight weeks. Clinical review was undertaken at weeks 4 and 8 and questions relating to symptoms and the incidence of headache were asked.Results:The median age of the 15 (8 male) patients was 6 years (range 3–13). There were 5 anterior and 10 posterior fissures. The median duration of symptoms was 9 (3–30) months. 13/15 (86.7%) patients were taking laxatives at the time of referral. Fissure healing was complete at 8 weeks in all seven patients who received 0.05% and in 5/8 (62.5%) patients using the 0.1% ointment (Fisher’s exact test, not significant). One patient from each arm experienced headaches during the first week of the trial which resolved without treatment and did not affect compliance. There were no other side effects.Conclusions:Topical glyceryl trinitrate ointment is effective in healing chronic anal fissures in children. Healing rates and side effect profile are comparable when either 0.05 or 0.1 per cent ointment is used.

Keywords: Adolescent, Child, Child, Preschool, Chronic Disease, Fissure in Ano - drug therapy, Nitroglycerin - therapeutic use, Ointments, Pilot Projects, Random Allocation, Time Factors