When a man is sexually stimulated, signals from the nervous system and the release of chemical messengers within the tissues of the penis allow him to have an erection.
One of these chemical messengers, called cyclic GMP, causes the blood vessels in the penis to widen by relaxing smooth muscle tissue. This results in more blood flow to the penis, making the penis larger and harder until full erection. Buy Levitra Plus
Cyclic GMP is normally regulated and constantly broken down by another chemical in the body called PDE-5. When there is more cyclic GMP than PDE-5, an erection results. Once the PDE-5 breaks down the cyclic GMP, the erection goes away. Generic pharmacy
Men with ED often cannot produce enough cyclic GMP. The little that is made is rapidly broken down by PDE-5, and blood flow is reduced, resulting in erectile failure. Canada pharmacy
Levitra is a PDE-5 inhibitor. It works by preventing the action of PDE-5, therefore stopping the breakdown of cyclic GMP.