Sildenafil works by inhibiting phosphodiesterase-5 (PDE5), an enzyme that breaks down cyclic guanosine monophosphate (cGMP). This allows cGMP levels to rise in the smooth muscle cells of the corpora cavernosa, the spongy tissue in the penis.
Elevated cGMP relaxes these smooth muscles, increasing blood flow into the penis. This increased blood flow is crucial for achieving and maintaining an erection.
The effect is specific to the penis because PDE5 is more concentrated there than in other parts of the body. Therefore, sildenafil’s impact on other systems is minimal at therapeutic doses.
Remember, sildenafil requires sexual stimulation to be effective; it doesn’t automatically cause an erection.
Its action is relatively short-lived, typically lasting several hours. The exact duration varies between individuals.
