RESUMEN
<p><b>AIM</b>To evaluate patient preferences for sildenafil citrate or tadalafil (PDE-5 inhibitors available for the treatment of erectile dysfunction [ED]) and assess potential reasons for these preferences.</p><p><b>METHODS</b>This open-label study was conducted on Korean men taking sildenafil, at least 6 weeks prior to study entry, for ED. Following screening, patients continued sildenafil treatment for 4 weeks, then after a 1-week washout period, switched to tadalafil for 8 weeks. Patients then continued with their treatment of choice during an extension phase. Psychosocial factors (time concern, spontaneity, sexual self-confidence) were evaluated using Psychological and Interpersonal Relationship Scales (PAIRS), while timing of dose to sexual attempt patterns were assessed from patient diaries.</p><p><b>RESULTS</b>The present study enrolled 160 Korean men (mean age 55 years) with prior median sildenafil use of 585 days. During the extension phase, 73.7% of patients elected to take tadalafil, whereas 26.3% chose sildenafil (P < 0.001). After switching from sildenafil to tadalafil, mean PAIRS time concern scores decreased from 2.54 to 2.42 (P = 0.002), with no statistically significant differences observed between the sildenafil and tadalafil assessment phases in sexual spontaneity and self-confidence scores. Sexual attempts made > 4 h to =/< 36 h post-dose occurred in 4.5% of patients during the sildenafil assessment phase compared with 17.5% during the tadalafil assessment phase.</p><p><b>CONCLUSION</b>After experiencing both sildenafil and tadalafil, the majority of patients exhibited a preference for tadalafil. This preference might be influenced by psychosocial factors, such as decreased time concerns, and a broader window of opportunity available for sexual activity.</p>