‘Reversible chemical sphincterotomy’ by local application of glyceryl trinitrate

Abstract

Nitric oxide has emerged as one of the most important neurotransmitters mediating internal anal sphincter relaxation. The effect of glyceryl trinitrate, a nitric oxide donor, on anal tone was examined. Maximum resting pressure, predominantly a function of the smooth muscle internal anal sphincter, was measured before and 20 min after application of 0.2 per cent glyceryl trinitrate ointment in ten patients. Pressure decreased by a mean of 27 per cent (95 per cent confidence interval 18-36 per cent) (P = 0.0004) after administration of the drug. A further 20 patients were then randomized to either active or placebo ointment. Anal pressure was significantly decreased (P = 0.002) in those who received 0.2 per cent glyceryl trinitrate, but there was no significant reduction in the control patients. Mild headache occurred in two patients who were given the active preparation and in one who received placebo. Manometry was repeated 9h after application of glyceryl trinitrate and showed a sustained decrease in pressure in two patients. Topical glyceryl trinitrate may have a role in the treatment of anal fissure, haemorrhoids, certain types of constipation and anal pain. It may also reduce injury to the internal sphincter during peranal operations.

Nifedipine Gel with Lidocaine in the Treatment of Anal Fissure in Children: A Pilot Study and Review of the Literature

“…Exogenous nitrates release nitric oxide in vivo and have been used clinically as nitric oxide donors. Loder et al (1994) demonstrated that topical application of 0.2% GTN led to decreased resting anal pressure. Chemical sphincterotomy using GTN with adjunctive stool softeners has been demonstrated to be quite effective at relieving symptoms and promoting healing.…”

What every gastroenterologist needs to know about common anorectal disorders

“…A significant reduction in anal pressure after soaking in warm water has been reported [34] . Based on the theory that anal fissures are caused by ischemia through a spasmodic internal sphincter, pharmacological agents including glyceryl trinitrate (GTN) [35][36][37] , diltiazem [35,[38][39][40] , and botulinum toxin may be useful. These agents have been employed to reduce the resting anal canal pressure and to improve blood flow, and as an alternative to surgical sphincterotomy for chronic fissures.…”

“…These agents have been employed to reduce the resting anal canal pressure and to improve blood flow, and as an alternative to surgical sphincterotomy for chronic fissures. GTN ointment applied two to four times per day to the anus has been the most extensively studied, resulting in various healing rates and the identification of a major side effect in dose-related headaches [36] . A randomized, controlled trial has shown that 0.2% nitroglycerin ointment applied twice daily healed chronic ulcers (68% compared with 8% in the placebo group) with evidence of a reduction in resting anal pressure and an increase in anoderm blood flow after eight weeks of treatment [37] .…”

A Brief Literature Review on the Management of Post-Haemorrhoidectomy Pain

“…Loder et al and Guillemot et al showed that topical application of nitroglycerin results in the lowering of the IAS in normal human patients. 40 It was thus popularly hypothesised that GTN and other nitrates can reduce pain by relaxing the IAS. Lund and Scholefield used 0.2% GTN ointment and showed that it decreased MARP by 33% and induced an increase in anodermal blood flow.…”

“…7 It has been shown that GTN works most effectively on the upper two-thirds of the anal canal and to a lesser extent on the lower third of the anal canal [40]. Various trials have shown that topical GTN is effective in promoting healing in patients with chronic anal fissures.…”