Viagra (sildenafil) primarily works by inhibiting phosphodiesterase-5 (PDE5), an enzyme that breaks down cyclic GMP. Increased cyclic GMP relaxes blood vessels, leading to improved blood flow to the penis, facilitating erections. This mechanism is relatively specific to the penis, but potential indirect effects on the prostate exist.
Prostate Blood Flow and Viagra
Since Viagra enhances blood flow, some men with benign prostatic hyperplasia (BPH) might experience improved urinary flow. However, this isn’t a guaranteed effect, and it’s not a treatment for BPH. Increased blood flow might also, in rare cases, worsen BPH symptoms or interact with existing BPH medication. Consult your doctor before using Viagra if you have BPH.
Potential Interactions and Considerations
Viagra can interact with certain medications, including those for heart conditions, high blood pressure, and BPH. Combining Viagra with nitrates can be dangerous, causing a significant drop in blood pressure. Always inform your doctor of all medications you are taking, including over-the-counter drugs and supplements. Regular monitoring of blood pressure is recommended during Viagra use.
Summary of Potential Prostate Impacts
| Improved urinary flow (for some with BPH) | Low to Moderate | Not a BPH treatment; consult your doctor. |
| Worsened BPH symptoms | Low | Monitor symptoms closely; discontinue if problems arise. |
| Interaction with BPH medication | Possible | Inform your doctor of all medications. |
Further Precautions
Men with a history of prostate cancer or other prostate conditions should discuss Viagra use with their urologist before starting treatment. This ensures safe usage and minimizes potential risks.


