How does Vidalista work? from chrismarshall5470's blog

The active ingredient in Vidalista Pills, tadalafil, increases blood flow to the penis, which results in an erection. Nitric oxide is released by the erectile tissue of the penis during sexual stimulation, and this triggers the guanylate cyclase enzyme. An erection is brought on by an increase in cyclic guanosine monophosphate (cGMP), which relaxes the blood vessels in the penis and allows blood to fill the spongy erectile tissues. An erection may end when another enzyme called phosphodiesterase type 5 (PDE5) breaks down cGMP and stops blood flow to the penis.