Randomized Clinical Trial of Botulinum Toxin Plus Glyceryl Trinitrate vs . Botulinum Toxin Alone for Medically Resistant Chronic Anal Fissure: Overall Poor Healing Rates

Abstract

There is some evidence to suggest that combining glyceryl trinitrate with botulinum toxin is superior to the use of botulinum toxin alone for glyceryl trinitrate-resistant anal fissure. The poor healing rate may reflect the fact that many of the patients did not have significant anal spasm at trial entry.

Patient factors do not predict symptomatic response to botulinum toxin for the treatment of anal fissure

“…A recent Cochrane review even concluded that there was no statistical advantage to Botox when compared to GTN. 5,7,[9][10][11] In contrast, our study has demonstrated that Botox therapy is effective treatment for both acute and chronic anal fissure with a response rate of 86.5% at a median follow up of 9 months.…”

“…In contrast to the mechanism of action of GTN, Botox mediated IAS relaxation is by a blockade of sympathetic neural output to the IAS and not by an effect on nitrenergeric transmission. [5][6][7] Based on the heterogeneity of the published fissure healing rates in response to Botox, our study aimed to assess fissure-healing rates with the use of Botox and to identify any factors, which were associated with successful outcome.…”

Conservative and Surgical Treatment of Chronic Anal Fissure: Prospective Longer Term Results

“…29,49,54 There is no consensus on dose, site, or number of injections. 55 However, a dosage between 20 and 25 units and anterior injection seems more effective and causes no additional side effects. 16,17,44,48,56,57 Despite healing rates as high as 90% for acute and chronic fissures shown by early trials, the enthusiasm was tempered by the disappointing results on CAF.…”

Medical and Surgical Treatment of Chronic Anal Fissure: A Prospective Study

“…26,41,42 There is no consensus on dose, site, or number of injections. 43 However, a dosage between 20 and 25U, and anterior injection seems more effective and causes no additional side effects. 14,15,37 A transient decrease in mean squeeze pressure can also be observed when higher doses are used.…”