title: Efficacy of cholestyramine ointment in reduction of postoperative pain and pain during defecation after open hemorrhoidectomy: results of a prospective, single-center, randomized, double-blind, placebo-controlled trial.
abstract: BACKGROUND
  The aim of the present study was to evaluate the efficacy of cholestyramine ointment (15 %) in reducing postoperative pain at rest and during defecation after open hemorrhoidectomy.
  
  
  METHODS
  A total of 91 patients with third and fourth degree hemorrhoids undergoing open hemorrhoidectomy were included in this prospective, double-blind, randomized controlled trial. The patients were randomly assigned to either cholestyramine ointment or placebo immediately after surgery, 12 h after surgery, and then every 8 h for 14 days. The primary outcomes were intensity of pain at rest and during defecation, measured with a visual analog scale, and the analgesic requirement, measured by amount of tramadol consumption.
  
  
  RESULTS
  The cholestyramine group had less postoperative pain than the placebo group at the 24th hour (1.84 ± 2.54 vs. 4.07 ± 3.35; P = 0.001) and 48th hour (0.18 ± 0.88 vs. 3.57 ± 3.45; P < 0.001) and less pain during defecation starting at the 48th hour (2.28 ± 2.96 vs. 4.77 ± 4.09; P = 0.001). Similarly, the average tramadol consumption at hours 24 and 48 was significantly lower for the cholestyramine group (5.32 ± 21.45 vs. 43.18 ± 61.56 mg at 24 h, and 4.48 ± 16.65 vs. 57.63 ± 65.47 mg at 48 h; P < 0.001). The only adverse event was pruritus, which had a lower frequency in the cholestyramine group but the difference was not significant until postoperative week 4 (P < 0.001).
  
  
  CONCLUSIONS
  Compared with placebo, cholestyramine ointment (15%) reduced postoperative pain at rest and on defecation, and consequently lowered the analgesic requirement after open hemorrhoidectomy.
authors.affiliation: Department of Clinical Pharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, 18th Kilometer Farahabad Boulevard, 48175861, Sari, Mazandaran Province, Iran. sh204ala@yahoo.com
authors.forename: Shahram
authors.initials: S
authors.lastname: Ala
authors.forename: Fariborz
authors.initials: F
authors.lastname: Eshghi
authors.forename: Reza
authors.initials: R
authors.lastname: Enayatifard
authors.forename: Payam
authors.initials: P
authors.lastname: Fazel
authors.forename: Banafsheh
authors.initials: B
authors.lastname: Rezaei
authors.forename: Roja
authors.initials: R
authors.lastname: Hadianamrei
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000837:Anion Exchange Resins / Q000008:administration & dosage; D002792:Cholestyramine Resin / Q000008:administration & dosage*; D003672:Defecation; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D061865:Hemorrhoidectomy / Q000379:methods*; D006484:Hemorrhoids / Q000175:diagnosis / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009824:Ointments / Q000627:therapeutic use; D010147:Pain Measurement / Q000187:drug effects; D010149:Postoperative Pain / Q000188:drug therapy* / Q000517:prevention & control; D011446:Prospective Studies; D012016:Reference Values; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000837:Anion Exchange Resins; D009824:Ointments; D002792:Cholestyramine Resin