Double blind randomised controlled trial of topical glyceryl trinitrate in anal fissure.

AIMS To determine the effectiveness and safety of topical glyceryl trinitrate (GTN) in the management of acute anal fissure in children. METHODS Individual children were randomised to receive GTN paste or placebo for six weeks in addition to oral senna and lactulose. Patients took laxatives alone for a further 10 weeks. Each week a research nurse telephoned families to assess pain scores and give advice. Main outcome measures were validated standardised pain scores and time to painless defaecation. RESULTS Forty subjects were recruited from 46 eligible children; 31 children completed the trial (13 in the GTN group and 18 in the placebo group). No differences in the proportion of those achieving pain free defaecation with relation to time were seen between the two groups. Similarly, there were no significant differences in pain scores between the two groups over the 16 week study period. However, in both groups pain scores had decreased significantly. There were no differences in the incidence of rectal bleeding, faecal soiling, presence of visible fissure, skin tag, or faecal loading at outpatient review at the time of recruitment, or at 6 weeks and 16 weeks. No serious adverse effects were observed. CONCLUSIONS This study suggests that 0.2% GTN paste is ineffective in the treatment of acute anal fissures in childhood. However the overall fissure healing rate is high (84%) with associated reduction in pain scores, suggesting that a nurse based treatment programme can achieve a high rate of fissure healing.