Measurement of plasma concentrations of yokukansan in form of suppository to healthy Japanese volunteers

INTERVENTION: Blood sampling time: before, and 0.5, 1, 2, and 4 hour after the enteric administration with 7.5g yokukansan Blood sampling time: before, and 0.5, 1, 2, and 4 hour after the oral administration with 7.5g yokukansan CONDITION: healthy Japanese volunteers PRIMARY OUTCOME: Time course of plasma levels of hirsuteine and geissoschizine methylether after enteric administration of yokukansan SECONDARY OUTCOME: Time course of plasma levels of hirsuteine and geissoschizine methylether after oral administration of yokukansan INCLUSION CRITERIA: a) Healthy volunteers b) Agreement to sign an informed consent