Vidalista 20 contains tadalafil, a medicine commonly used to treat erectile dysfunction (ED). It works by improving blood flow to the penis when sexual stimulation occurs, helping men achieve and maintain an erection. Tadalafil belongs to a group of medicines called PDE5 inhibitors and may provide effects for up to 36 hours. Vidalista 20 does not increase sexual desire and will not cause an erection without stimulation.