Viagra, or sildenafil, works by inhibiting an enzyme called phosphodiesterase-5 (PDE5).
PDE5 breaks down cGMP, a molecule crucial for achieving and maintaining an erection. By blocking PDE5, Viagra allows cGMP levels to remain high. This increased cGMP leads to relaxation of smooth muscles in the penis, increasing blood flow and facilitating an erection.
The process is triggered by sexual stimulation. Sexual stimulation releases nitric oxide, which then triggers the production of cGMP. Viagra enhances this natural process by preventing the cGMP from being broken down too quickly.
It’s important to understand Viagra doesn’t directly cause erections; it facilitates them in response to sexual stimulation. Without sexual stimulation, Viagra won’t induce an erection.
| Sexual Stimulation | Nitric oxide release |
| Nitric Oxide | Increases cGMP levels |
| Viagra (PDE5 Inhibition) | Prevents cGMP breakdown |
| Increased cGMP | Penile smooth muscle relaxation |
| Relaxed Muscles | Increased blood flow |
| Increased Blood Flow | Erection |
This mechanism explains why Viagra is effective for treating erectile dysfunction. However, individual responses vary, and consulting a doctor before using Viagra is always recommended.
