Viagra is typically taken in pill form approximately 30 minutes to an hour before sexual activity, and its effects can last for up to four hours. It is important to note that sexual stimulation is required for viagra keep you hard to be effective. The medication does not increase sexual desire, but rather assists in the physiological process of achieving an erection. The active ingredient in Viagra, sildenafil citrate, belongs to a class of drugs known as phosphodiesterase type 5 (PDE5) inhibitors.
Nitric oxide activates an enzyme that produces cyclic guanosine monophosphate (cGMP), a substance that relaxes smooth muscle cells, allowing blood to flow freely and cause an erection. PDE5 is an enzyme found in various tissues, including the smooth muscle cells of blood vessels and the corpus cavernosum, a sponge-like area around the penis that fills with blood during an erection. Under normal circumstances, after sexual stimulation, sildenafil citrate tablets 100mg the body releases nitric oxide into the corpus cavernosum.
Nitric oxide is a naturally occurring compound in the body that plays a key role in the initiation and maintenance of an erection. This compound relaxes smooth muscle tissue, allowing increased blood flow into the penis, leading to an erection. The mechanism of action of Viagra centers on its effects on the nitric oxide (NO) pathway. During sexual stimulation, NO is released in the corpus cavernosum, a cylindrical tissue in the penis.
NO activates an enzyme called guanylate cyclase, which increases levels of cyclic guanosine monophosphate (cGMP). The clinical efficacy of Viagra has been demonstrated in numerous studies. However, the effectiveness of Viagra can be influenced by certain factors such as the presence of food in the stomach, particularly high-fat meals, which can delay the onset of action. Typically, Viagra is taken about one hour before sexual activity, and its effects can last for up to four hours.
It is effective in various populations of men with ED, including those with diabetes mellitus, spinal cord injury, and other conditions. It is contraindicated in patients who are taking nitrates (often prescribed for chest pain), as the combination can cause a dangerous drop in blood pressure. In rare cases, Viagra can cause more serious side effects like priapism, a prolonged and painful erection that can cause permanent damage if not treated promptly.
While Viagra has proven to be highly effective in treating ED, it is not suitable for everyone. Other potential side effects include headaches, flushing, indigestion, nasal congestion, dizziness, and visual disturbances. PDE5, however, breaks down cGMP, thus inhibiting the ability to achieve or maintain an erection. By inhibiting PDE5, Viagra effectively increases the levels of cGMP, enhancing and prolonging erections in men suffering from ED. The drug is effective only with sexual stimulation, as it relies on the initial release of nitric oxide by the body.
Its introduction was a major breakthrough and it has since become a cultural phenomenon, often discussed openly in the media and in popular culture, which was unusual for any medication related to sexual health before its advent. Introduced to the market in 1998, Viagra was the first oral treatment approved by the FDA for erectile dysfunction. In conclusion, Viagra represents a landmark discovery in the field of sexual medicine.
