Delayed ejaculation is a side effect of selective serotonin reuptake inhibitors (SSRIs) in men. Dapoxetine, a short-acting SSRI, is the first drug marketed for premature ejaculation. After oral administration, peak plasma concentrations of dapoxetine are achieved within one hour. The elimination is relatively rapid and the terminal half-life is about 19 hours. Ever long tablet randomized controlled trials have been performed for premature ejaculation.1-6 The primary outcome of most studies was the "intravaginal ejaculation phase" that the partner measures by using the stopwatch. In two studies (1) in which 2614 men (18-77 years of age) were randomized to dapoxetine (30 mg or 60 mg) or placebo (all 1-3 hours before intercourse), it was found that dapoxetine significantly increased the intravaginal ejaculation time than the placebo. The starting point for men was at least 2 minutes or less than 75% intravaginal ejaculation latency. After 12 weeks, 29% of the 30 mg dose t