title: The role of antileukotriene therapy in seasonal allergic rhinitis: a systematic review of randomized trials.
abstract: OBJECTIVE
  To evaluate the effect of oral leukotriene receptor antagonists as monotherapy or combined with other drugs in the treatment of seasonal allergic rhinitis.
  
  
  METHODS
  The MEDLINE, EMBASE, CINAHL (Cumulative Index to Nursing and Allied Health), and Cochrane databases; review articles; and references of included trials.
  
  
  METHODS
  Published (1966-2005) randomized controlled trials with nasal and eye symptoms and quality-of-life scores as primary outcomes.
  
  
  RESULTS
  Seventeen studies including 6,231 adults with seasonal allergic rhinitis were selected. Oral leukotriene antagonists significantly reduced daytime nasal symptoms (standardized mean difference [SMD], -0.24; 95% confidence interval [CI], -0.33 to -0.16), nighttime nasal symptoms (SMD, -0.23; 95% CI, -0.30 to -0.16), and eye symptoms and significantly improved quality of life compared with placebo. There were no significant differences between oral leukotriene antagonists and oral histamine H1 antagonists on nasal and eye symptoms and quality-of-life overall score. We also found that leukotriene receptor antagonists were inferior to intranasal corticosteroids for decreasing daytime (SMD, 0.41; 95% CI, 0.27 to 0.56) and nighttime nasal symptoms. The combination of leukotriene receptor antagonists plus histamine H1 antagonists produced greater relief of eye symptoms compared with histamine H1 antagonists alone. Finally, intranasal corticosteroids significantly reduced nasal congestion compared with leukotriene receptor antagonists plus histamine H1 antagonists.
  
  
  CONCLUSIONS
  Leukotriene receptor antagonists were better than placebo, equivalent to oral histamine H1 antagonists, and inferior to intranasal corticosteroids for treating seasonal allergic rhinitis. Alternatively, leukotriene receptor antagonists plus histamine H1 antagonists were more effective than histamine H1 antagonists alone but inferior to intranasal corticosteroids.
authors.affiliation: Departamento de Emergencia, Hospital Central de las Fuerzas Armadas, and Clinica Respirar, Benito Nardone, Montevideo, Uruguay. gurodrig@adinet.com.uy
authors.forename: Gustavo J
authors.initials: GJ
authors.lastname: Rodrigo
authors.forename: Anahi
authors.initials: A
authors.lastname: Yañez
mesh_terms: D000281:Administration, Intranasal; D000284:Administration, Oral; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D006634:Histamine H1 Antagonists / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D020024:Leukotriene Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D015201:Meta-Analysis as Topic; D016032:Randomized Controlled Trials as Topic; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy*
chemical_list: D000305:Adrenal Cortex Hormones; D006634:Histamine H1 Antagonists; D020024:Leukotriene Antagonists