Vidalista is a medication primarily used to treat erectile dysfunction (ED) and contains the active ingredient tadalafil, a phosphodiesterase type 5 (PDE5) inhibitor. Vidalista mechanism of action involves blocking the PDE5 enzyme, which is responsible for breaking down cyclic guanosine monophosphate (cGMP) in the smooth muscle cells lining the blood vessels of the penis. When sexual stimulation occurs, nitric oxide (NO) is released, stimulating the production of cGMP. Higher cGMP levels cause smooth muscle relaxation and vasodilation, increasing blood flow to the corpus cavernosum and resulting in an erection. Tadalafil's effects can last up to 36 hours, offering a longer therapeutic window compared to other ED drugs.