The effect of nedocromil sodium on nasal provocation with allergen.

We have investigated the effect of nedocromil sodium in preventing the symptoms of rhinitis occurring immediately after allergen provocation in 10 patients with allergic rhinitis. The study had a double-blind, placebo-controlled, crossover design. Nedocromil sodium (1% w/v) and placebo were administered intranasally from identical metered-dose inhalers 20 minutes before allergen provocation. Three variables were measured: nasal airway resistance, the production of secretion, and the number of sneezes. Nedocromil sodium was significantly more effective than placebo in preventing nasal obstruction (p less than 0.01), rhinorrhea (p less than 0.01), and sneezing (p less than 0.05), suggesting that this drug may be useful in the treatment of allergic rhinitis.