title: Topical anal fissure treatment: placebo-controlled study of mononitrate and trinitrate therapies.
abstract: OBJECTIVE
  The present study aims to evaluate and compare the efficacy of two nitrate gels, containing isosorbide-5-mononitrate (ISMN) or glyceryl trinitrate (GTN), in the therapy of chronic anal fissure.
  
  
  METHODS
  The patients were randomly assigned to three groups: 0.1% ISMN gel (21 patients), 0.1% GTN gel (21 patients) and a placebo group (ten patients). The ethic committee of our hospital approved the protocol and informed consent was obtained from all participants. All patients underwent clinical examination, visual inspection of the fissure and anal manometry prior to and after therapy.
  
  
  RESULTS
  The chronic anal fissure was completely healed in 71% of the patients treated with ISMN, 67% with GTN and in 30% from the placebo group. One patient in the ISMN group reported mild headache. Three patients in the GTN group had anal burning.
  
  
  CONCLUSIONS
  Both topical nitrate treatments (ISMN and GTN) were effective for chronic anal fissures. The reduction of the anal pressure was slightly higher after ISMN treatment (28%) than the treatment with GTN (23%). However, the statistical difference was not significant (p>0.05).
authors.affiliation: Clinical Centre of Gastroenterology, State University Hospital Queen Joanna, 8 Bialo more Str., 1527 Sofia, Bulgaria.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Tankova
authors.forename: Krassimira
authors.initials: K
authors.lastname: Yoncheva
authors.forename: Daniel
authors.initials: D
authors.lastname: Kovatchki
authors.forename: I
authors.initials: I
authors.lastname: Doytchinova
mesh_terms: D000287:Administration, Topical; D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005401:Fissure in Ano / Q000188:drug therapy*; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage* / Q000627:therapeutic use*; D010919:Placebos; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000008:administration & dosage* / Q000627:therapeutic use*
chemical_list: D010919:Placebos; D014665:Vasodilator Agents; D005996:Nitroglycerin; D007548:Isosorbide Dinitrate; C030397:isosorbide-5-mononitrate