Finasteride lowers the levels of a hormone that can contribute to the growth of prostate cancer.
These latest recommendations were based on 15 studies dating back to 2003. Men would need to take the drug for seven years to avoid getting prostate cancer.
The American Cancer Society says the drug is a reasonable option but it's important to note that there is no conclusive evidence that using finasteride can reduce the risk of death from prostate cancer.
