"Although the phosphodiesterase-5 inhibitor sildenafil shows evidence of efficacy and tolerability...Attitudes Toward Placebo Use in LebanonAvailable online 23 March 2015Fadi Abou-Mrad | Lubna TarabeyPlacebo use, both in clinical trials and patient care, is a problematic ethical issue surrounded by opposing arguments from those who advocate its use versus those who do not." . . . . .