Viagra is a PDE inhibitor, used for the treatment of erectile dysfunction, one of the most common sexual disorders experienced by men. Impotence, as it is also known, is known to affect nearly 2.3 million men in the UK. It is a condition which causes you to face difficulty in achieving or sustaining an erection while engaged in a sexual act. When a man is sexually aroused, his brain sends signals to the NANC cells in the arteries, which in turn release nitric oxide, an anti-atherosclerotic agent. Nitric oxide signals and stimulates the release of an enzyme called guanylate cyclase. This enzyme is responsible for conversion of the chemical GTP into cyclic GMP (cGMP).
The chemical cGMP causes the inner muscles of the penile arteries to relax, in turn increasing the blood flowing to the organ. The increase in blood flow to your sex organ causes it to expand and inflate, resulting in an erection. As the sexual stimulation starts to decrease, another chemical, PDE, is released, which starts breaking down cGMP, converting it back in to GTP and making your sex organ flaccid again. Men usually develop erectile problems when there is a decrease in the blood flowing to their sex organ. Viagra, a treatment for erectile dysfunction, contains sildenafil citrate, which plays the major role in treating this condition. It attaches to the PDE molecules and breaks them down so as to stop them from affecting the cGMP molecules.
As the sildenafil affects the PDE molecules, cGMP remains in your body and its functioning is enhanced. Thus, men using this medication have been able to experience significant improvements in their sexual experience. For ensuring your sexual pleasures, it is recommended that you take the pill around 30 to 60 minutes prior to engaging in a sexual act. The effects of this pill are known to last for four hours. However, be warned that taking the pill more than once within 24 hours may increase the risk of side effects such as headaches, vomiting, back pain, facial flushing and nasal congestion.