After taking Vidalista 20 mg, which contains the active ingredient Tadalafil, several things typically happen to help treat erectile dysfunction. By inhibiting PDE5, Tadalafil helps maintain higher levels of cGMP, leading to the relaxation of smooth muscle and increased blood flow to the penis during sexual arousal. When sexually aroused, the increased blood flow to the penis helps men achieve and maintain an erection. Vidalista 20 mg does not cause spontaneous erections. You will still need to be sexually stimulated for the medication to work. Vidalista 20 mg is typically effective for up to 36 hours, giving you a longer window of opportunity to engage in sexual activity without needing to take additional doses.