A Multicenter, Open Label, To Evaluate The Efficacy And Satisfaction Of Patrex® In Men With Erectile Dysfunction.

Tablets, 50mg and 100mg , Medication will be taken orally with a glass of water approximately one hour (30 min to 4 hours) before sexual activity. Subjects are to take one dose in any calendar day.Eligible patients fulfilling all inclusion/exclusion criteria will be assigned at Visit 2/Week 0 (Baseline) to receive sildenafil 50 mg as needed (PRN) during the first two weeks, and,thereafter, at Visit 3/Week 2, all enrolled subjects will be up titrated to sildenafil 100 mg PRN for the following four weeks.