Efficacy of pollen blocker cream in the treatment of allergic rhinitis.

OBJECTIVE To assess the efficacy and safety of a pollen blocker crème for prophylaxis of symptoms in patients with seasonal or perennial allergic rhinitis. DESIGN Double-blind, randomized, placebo-controlled, crossover study conducted from November 2001 through September 2002 in 2 outpatient centers in Germany and 1 in Russia. Ninety-one patients aged 18 to 55 years with at least a 2-year history of seasonal or perennial allergic rhinitis confirmed by history and positive skin test results were randomly assigned to receive pollen blocker cream (n = 43) or carboxymethylcellulose in gel (placebo) (n = 48) applied sparingly to the lower internal nose region 4 times daily for a total of 9 days. The efficacy of treatment was assessed by means of nasal provocation testing. The investigators assessed the nasal symptom severity scores (range, 0-6), and the changes in nasal airflow after allergen application were measured by anterior rhinomanometry. RESULTS The median score fell from 4 to 1 after application of the pollen blocker cream (P<.001) and from 4 to 3 in the placebo group (P<.05). The difference between the 2 groups after the second provocation was highly significant (P<.001). The increase in airflow in response to treatment was roughly 20% in the blocker group compared with only about 10% in the placebo group, relative to an airflow rate (299 mL/s) measured after provocation on day 1. CONCLUSIONS The blocker was significantly more effective than placebo and reduced the typical symptoms of allergic rhinitis in response to nasal challenge with allergen by nearly 60% (placebo reduced symptoms by 25%). The pollen blocker cream did not produce any adverse effects. Therefore, the efficacy of the investigational product can be rated as good.