Purpose: We evaluate the efficacy of paroxetine hydrochloride as needed for the treatment of premature ejaculation.
Materials and method: Study 1 comprised 26 potent men with a mean age of 39.5 years with premature ejaculation who were randomized to receive 20 mg. oral paroxetine (group A) or placebo (group B) as needed 3 to 4 hours before planned intercourse in a controlled single-blind crossover trial. Study 2 comprised 42 potent men with a mean age of 40.5 years with premature ejaculation who were randomized to receive 10 mg. paroxetine daily for 3 weeks and then 20 mg. paroxetine as needed (group C) for 4 weeks or placebo daily for 3 weeks and then placebo as needed (group D) for 4 weeks.
Results: Mean pretreatment ejaculatory latency time was 0.3 minute for study 1. At 4 weeks mean ejaculatory latency time was 3.2 minutes in the paroxetine as needed and 0.45 in the placebo as needed phase for group A (p < 0.001), and 0.6 in the placebo as needed and 3.5 in the paroxetine as needed phase for group B (p < 0.001). There were no adverse effects with paroxetine or placebo in study 1. Mean pretreatment ejaculatory latency time was 0.5 minute for study 2. At 3 weeks mean ejaculatory latency time was 4.3 minutes in the paroxetine daily and 5.8 in the paroxetine as needed phase, and 0.9 in the placebo daily and 0.6 in the placebo as needed phase for group C (p < 0.001). At 3 weeks mean ejaculatory latency time was 0.8 minutes in the placebo daily and 1.1 in the placebo as needed phase, and 3.3 in the paroxetine daily and 6.1 in the paroxetine as needed phase for group D (p < 0.001). Adverse effects in 7 of 42 men (17%) given paroxetine daily included an ejaculation in 3, anorexia in 1, gastrointestinal upset in 3 and reduced libido in 2. Mean ejaculatory latency time was greater in the paroxetine as needed phase of study 2 than that of study 1 (p < 0.05), suggesting that ejaculatory control achieved with paroxetine as needed is significantly better if patients are initially treated with the drug daily.
Conclusions: Paroxetine appears to be superior to placebo in the pharmacological treatment of premature ejaculation when administered on a chronic or as needed basis.