title: Topical treatments for seasonal allergic conjunctivitis: systematic review and meta-analysis of efficacy and effectiveness.
abstract: BACKGROUND
  Evidence for the effectiveness of topical treatments, in providing symptomatic relief from ocular allergy, remains uncertain.
  
  
  OBJECTIVE
  To assess the effectiveness and relative efficacy of topical treatments for the management of seasonal allergic conjunctivitis.
  
  
  METHODS
  A systematic review and meta-analysis.
  
  
  METHODS
  A literature search of the Cochrane Library, Medline, and EMBASE bibliographic databases.
  
  
  METHODS
  Double-masked randomised controlled trials were identified, that compared the use of topical mast cell stabilisers (sodium cromoglycate, nedocromil, lodoxamide) with placebo, topical antihistamines with placebo, and topical mast cell stabilisers with topical antihistamines.
  
  
  RESULTS
  A meta-analysis of six trials showed that patients using sodium cromoglycate were 17 times (95% confidence interval [CI] = 4 to 78) more likely to perceive benefit compared with those using a placebo, although this estimate may be partially influenced by publication bias. Five trials indicated that those patients using nedocromil were 1.8 times (95% CI = 1.3 to 2.6) more likely to perceive their allergy to be moderately or totally controlled than those using a placebo. Four trials showed that those using antihistamines were 1.3 times (95% CI = 0.8 to 2.2) more likely to perceive a 'good' treatment effect than those using mast cell stabilisers, although this beneficial effect was not statistically significant. Limited evidence suggests that antihistamines might have a faster therapeutic effect compared to mast cell stabilisers.
  
  
  CONCLUSIONS
  Overall, these findings confirm the benefit of topical mast cell stabilisers and antihistamines over placebo for the treatment of allergic conjunctivitis. There is, however, insufficient evidence to recommend the use of one type of medication over another. Treatment preferences should therefore be based on convenience of use (with reduced frequency of instillation for some preparations), patient preference, and costs, especially as important side effects were not reported with any medication.
authors.affiliation: Department of Community Health Sciences, St George's Hospital Medical School, London. c.woen@sghms.ac.uk
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Owen
authors.forename: Anupa
authors.initials: A
authors.lastname: Shah
authors.forename: Katherine
authors.initials: K
authors.lastname: Henshaw
authors.forename: Liam
authors.initials: L
authors.lastname: Smeeth
authors.forename: Aziz
authors.initials: A
authors.lastname: Sheikh
mesh_terms: D000287:Administration, Topical; D003233:Conjunctivitis, Allergic / Q000188:drug therapy*; D003430:Cross-Sectional Studies; D006634:Histamine H1 Antagonists / Q000008:administration & dosage; D006801:Humans; D008407:Mast Cells / Q000187:drug effects; D016032:Randomized Controlled Trials as Topic; D019141:Respiratory System Agents / Q000008:administration & dosage*; D012621:Seasons; D016896:Treatment Outcome
chemical_list: D006634:Histamine H1 Antagonists; D019141:Respiratory System Agents