Dapoxetine and Sildenafil are mixtures of two medicines: Sildenafil and Dapoxetine, which use male erectile dysfunction and premature ejaculation. So, Sildenafil is a phosphodiesterase type 5 inhibitor that improves blood flow to the penis during sexual stimulation and enables its erection following sexual stimulation. So, Dapoxetine is a selective serotonin reuptake inhibitor that increases the serotonin levels in nerves to increase the time taken to ejaculate and improve control over ejaculation.