The combination of sildenafil/dapoxetine is used in the treatment of erectile dysfunction and premature ejaculation. Sildenafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors which relax muscles and increase blood flow to specific areas of the body, including the penis to produce and sustain an erection during sexual intercourse. Dapoxetine prolongs ejaculation and thereby helps with premature ejaculation.