A study of the effect of syoseiryuto on Japanese cedar pollinosis (randomized, placebo-controlled, double-blind study using the envionmental challenge chamber)

INTERVENTION: Intake of shoseiryuto for 2 weeks Intake of placebo for 2 weeks CONDITION: Japnese cedar pollinosis PRIMARY OUTCOME: Total nasal symptoms induced in the environmental challernge chamber after intake of the intervention drug for 2 weeks. SECONDARY OUTCOME: Association between "syo" and effect of the Shoseiryuto INCLUSION CRITERIA: 1)Patients who have medical history of cedar pollinosis for more than 2 years. 2)Patients who do not have nasal symtoms induced by any allergen and requier any drug treatment out of Japanese cedar pollen scattering season. 3)Positive specific IgE to cedar pollen allergen(>=class2) 4)Patients who develop more than moderate symptoms by a pollen exposure for 3 hours