title: Zafirlukast has no beneficial effects in the treatment of chronic urticaria.
abstract: BACKGROUND
  Leukotriene receptor antagonists have shown some efficacy in t he treatment of asthma. Injection of LTC4, LTD4 and LTE4 into the skin leads to a weal-and-flare reaction, suggesting an involvement of leukotrienes in the pathogenesis of urticaria. Indeed, various reports have indicated a beneficial effect for leukotriene receptor antagonists in patients with chronic urticaria.
  
  
  OBJECTIVE
  To determine the therapeutic effect of the leukotriene receptor antagonist zafirlukast in patients with chronic urticaria.
  
  
  METHODS
  The study was a double-blind, placebo-controlled, cross-over study lasting for 12 weeks. Fifty-two patients with chronic urticaria were investigated at a university hospital. The patients were randomized to receive 20 mg zafirlukast b.i.d. or placebo and cross-over was scheduled after 6 weeks. The efficacy of the treatment was evaluated by a daily symptom score, six physical examinations, the requirement of rescue antihistamines (acrivastine) and an overall assessment by the patient andthe investigating physician.
  
  
  RESULTS
  Forty-six patients completed the study: zafirlukast was well tolerated without alteration of the investigated laboratory parameters. In comparison with placebo, treatment with zafirlukast resulted in no significant positive effect for any of the efficacy measures. Moreover, we were unable to identify any subgroup of patients with chronic urticaria responding with a therapeutic benefit.
  
  
  CONCLUSIONS
  The leukotriene receptor antagonist zafirlukast does not provide a significant therapeutic benefit at a dose of 20 mg b.i.d. in patients with chronic urticaria.
authors.affiliation: Medial Division, Zieglerspital Bern, Bern, Switzerland. andrea.reimers@spitalbern.ch
authors.forename: A
authors.initials: A
authors.lastname: Reimers
authors.forename: C
authors.initials: C
authors.lastname: Pichler
authors.forename: A
authors.initials: A
authors.lastname: Helbling
authors.forename: W J
authors.initials: WJ
authors.lastname: Pichler
authors.forename: N
authors.initials: N
authors.lastname: Yawalkar
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006634:Histamine H1 Antagonists / Q000008:administration & dosage; D006801:Humans; D007211:Indoles; D020024:Leukotriene Antagonists / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D048448:Phenylcarbamates; D013449:Sulfonamides; D014105:Tosyl Compounds / Q000627:therapeutic use*; D016896:Treatment Outcome; D014311:Triprolidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D014581:Urticaria / Q000188:drug therapy*
chemical_list: D006634:Histamine H1 Antagonists; D007211:Indoles; D020024:Leukotriene Antagonists; D048448:Phenylcarbamates; D013449:Sulfonamides; D014105:Tosyl Compounds; D014311:Triprolidine; C043648:acrivastine; C062735:zafirlukast