title: A randomized, double-blind, placebo-controlled, controlled antigen delivery study of the onset of action of aerosolized triamcinolone acetonide nasal spray in subjects with ragweed-induced allergic rhinitis.
abstract: BACKGROUND
  Clinically apparent relief of nasal symptoms of allergic rhinitis is generally recognized to occur within 3 days to 1 week when intranasal corticosteroids are used.
  
  
  OBJECTIVE
  A study was designed to evaluate the onset of action of triamcinolone acetonide (TA) in patients with ragweed-induced allergic rhinitis with an environmental exposure unit (EEU).
  
  
  METHODS
  Eighty-five adults with ragweed-induced allergic rhinitis were primed with ragweed allergen in the EEU. Symptoms were recorded during a baseline exposure in the EEU, and subjects were randomized with a 5:1 ratio to receive either TA 400 micrograms (n = 71) or its propellant (n = 14). Subjects received study medication for 7 days under supervision in the morning and returned to the EEU in the evening for ragweed allergen challenge and symptom assessment. Clinically apparent onset of action was defined as a 25% decrease in symptom scores from baseline.
  
  
  RESULTS
  A mean reduction in nasal congestion from baseline of greater than 25% (onset of action) was observed in the TA group, but not in the placebo group, by 10 hours. This was also observed for itching of the nose or palate and a combined measure of symptoms. In addition, the proportion of subjects with less nasal congestion after 1 day of treatment was greater in the TA group (41%) than in the placebo group (7%) (p less than 0.05).
  
  
  CONCLUSIONS
  The unexpected early relief of symptoms observed in the TA group and, to a lesser extent in the placebo group, has important clinical implications in the treatment of allergic rhinitis.
authors.affiliation: Queen's University, Kingston, Ontario, Canada.
authors.forename: J H
authors.initials: JH
authors.lastname: Day
authors.forename: D L
authors.initials: DL
authors.lastname: Buckeridge
authors.forename: R H
authors.initials: RH
authors.lastname: Clark
authors.forename: M P
authors.initials: MP
authors.lastname: Briscoe
authors.forename: R
authors.initials: R
authors.lastname: Phillips
mesh_terms: D000281:Administration, Intranasal; D000293:Adolescent; D000328:Adult; D000336:Aerosols; D000485:Allergens / Q000008:administration & dosage*; D004311:Double-Blind Method; D004784:Environmental Monitoring; D005260:Female; D006801:Humans; D008297:Male; D011058:Pollen / Q000276:immunology*; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy* / Q000209:etiology*; D013997:Time Factors; D014222:Triamcinolone Acetonide / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D000336:Aerosols; D000485:Allergens; D014222:Triamcinolone Acetonide