We evaluate the efficacy and safety of citalopram, a potent and highly selective serotonin reuptake inhibitor (SSRI) antidepressant, in patients with premature ejaculation (PE). In total, 58 potent men with PE were included in the study. Patients were randomly assigned to receive 20 mg oral daily citalopram (group 1, n = 29) or placebo (group 2, n = 29), during a 12-week period for each agent. Pretreatment evaluation included history and physical examination, intravaginal ejaculatory latency time (IVELT) evaluation, International Index of Erectile Function (IIEF) and Meares-Stamey test. The efficacy of two treatments was assessed every 2 weeks during treatment, at the end of study and in 3- and 6-month follow-up after cessation of treatment, using responses to IIEF, IVELT evaluation, mean intercourse satisfaction domain, mean weekly coitus episodes and adverse drug effects. The trial was completed by 51 (88%) men. Analysis revealed a difference in the evolution of IVELT delay over time (P < 0.001). The IVELT after citalopram and placebo gradually increased from 32 and 28 s to approximately 268 and 38 s, respectively. The mean weekly intercourse episodes increased from pretreatment values of 1.3 and 1.2 to 2.4 and 1.4, for citalopram and placebo, respectively (P < 0.05). Baseline mean intercourse satisfaction domain values of IIEF 10 and 11 reached to 16 and 10 at 12-week treatment in groups 1 and 2, respectively (P < 0.05). Mean IVELT in group 1 was 210 and 198 s at 3- and 6-month follow-up, while in group 2 it was 27 and 25 s (P < 0.001), respectively. At 3- and six-month intercourse satisfaction domain values of IIEF were 15 and 14 in group 1 and 10 and 10 (P < 0.05) in group 2, respectively. Group 1 patients reported a significantly higher number of intercourse episodes per week (P < 0.05). Mean number of adverse events was 12 for citalopram and 4 for placebo (P < 0.05). In conclusion, these results indicate that citalopram has significantly better results in terms of IVELT and intercourse satisfaction versus placebo. Further studies with different dosages and treatment regimens are necessary to draw final conclusions on the efficacy of this drug in PE and to prolong the efficacy.