Efficacy of Alegysal in Relation to the Amount of Japanese Cedar and Japanese Cypress in the Air.

Cedar pollinosis patients who visited 21 medical facilities in the Tokai Region during the cedar and hinoki (Japanese cypress) pollen season in 1995 and 1996 were divided into two groups; one group which received Alegysal® before the pollen season started (pre-group) and a second group which received the drug after the start of the season (post-group). In 1995, in which an unusually large amount of pollen was scattered, the following symptoms were significantly less in the pregroup than in the post-group; sneezing at the beginning of the season and 2 weeks after the beginning of the season, nasal discharge, and nasal obstruction at the beginning of the season. Same symptoms were also significantly less in the pre-group than in the post-group in 1996, in which the amount of pollen scattered was less than in a typical year, including nasal obstruction at the beginning and 2 and 4 weeks after the beginning of the season. These findings suggest that it is in the interest of patients to initiate treatment before the season if large amounts of pollen are anticipated, although the amount of pollen did not seem to significantly affect the utility of preseason treatment.