Sakurai T, et al. - Researchers investigated the associations between the pollen dispersal pattern, allergic rhinitis symptom severity, and treatment efficacy in 4 randomized, placebo-controlled studies of sublingual immunotherapy (SLIT) on patients with Japanese cedar-induced allergic rhinitis who lived in or around Chiba, Japan. They used the Durham method to quantify the amount of pollen dispersed daily and based on the pollen count, divided the season into early and late periods. They observed a minimal impact of the fluctuation of daily pollen dispersal on the severity of symptoms during the late period. During this period, SLIT induced remarkable reduction in symptoms which was not seen in the early period.