Viagra 100mg

Viagra, known generically as sildenafil, is a prescription medication primarily used to treat erectile dysfunction (ED) in men. It belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors. The mechanism of action involves the inhibition of the PDE5 enzyme, which leads to an increase in cyclic GMP levels in the corpus cavernosum of the penis. This increase promotes relaxation of smooth muscle and enhances blood flow, facilitating an erection when sexual stimulation occurs.

How Does Viagra Work?

When a man is sexually aroused, signals from the brain lead to the release of nitric oxide in the penis. Nitric oxide stimulates the production of cyclic GMP, which relaxes blood vessels and allows for increased blood flow into the penis. Normally, PDE5 breaks down cyclic GMP, leading to a decrease in blood flow and loss of erection. Viagra inhibits this enzyme, allowing cyclic GMP to persist longer and thus prolonging the erection.

Dosage and Administration

Viagra is typically taken orally in tablet form and is available in three strengths: 25 mg, 50 mg, and 100 mg. The usual starting dose for most men is 50 mg, taken approximately one hour before sexual activity. It can be taken anywhere from 30 minutes to four hours prior to intercourse but should not be taken more than once daily. It’s important to note that taking Viagra with a high-fat meal may delay its effectiveness.