Inclusion Criteria:  1- Adult patients (aged 19-50 years) 2- Complaining from PMD with no or mild LUTS (IPSS<8).  Exclusion Criteria:  1- Patients with penile or urethral malformations 2- Patients recently received PDE5Is in the last 4 weeks prior to study start. 3- Systemic illness 4- Contraindications to PDE5Is. 5- History of pelvic surgery or irradiation 6- History of bladder or prostate surgery 7- Other acute medical conditions as acute gastroenteritis, osetoarthritis that might influence the patient QoL