2-period, 2 cross (2x2) crossover design was used. screened 12 subjects (males and females) were randomly divided into two groups (II-1、II-2), each 3 males and 3 females, give the following two different crossover treatments: trazodone hydrochloride prolonged-release tablets 150 mg per day for 7 days in T group, trazodone hydrochloride tablets 50mg for 3 times per day for 7 days in R group. Wash-out period is 14 days.