Examples

How It Works

Finasteride interferes with the effect of male hormones (androgens) on the prostate gland, which cause the prostate to become larger. This stops the growth of the prostate and can even cause it to become smaller. Stopping the growth of the prostate or reducing its size may help relieve pain or urination problems caused by prostatitis.

Why It Is Used

Finasteride may be prescribed for men who have prostatitis (especially chronic prostatitis/pelvic pain syndrome, inflammatory) and who also have moderate symptoms of prostate enlargement.

How Well It Works

Some studies have shown that finasteride can help with symptoms of prostatitis. But in other studies, finasteride didn't improve symptoms any more than placebo.¹

Side Effects

Side effects may include:

• Decreased sex drive.
• Reduced ejaculatory volume.
• Difficulty getting an erection, though sexual activity before the study was not evaluated.

It is possible that finasteride is linked to an increased risk for high-grade prostate cancers. But more research is needed.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

This medicine should not be used by men who may father a child, because it may cause birth defects in male babies. Women who are pregnant or might become pregnant should not handle crushed finasteride tablets. There is a small chance that the medicine could get into the woman's system and cause a birth defect.

Finasteride reduces prostate-specific antigen (PSA) levels. Because PSA levels are used to detect early-stage prostate cancer, men interested in taking finasteride might consider the following:

• Some experts suggest that men be checked for the presence of prostate cancer (using the PSA test and a digital rectal exam) before starting to take finasteride.
• Follow-up PSA tests that have not decreased by approximately 50% after 6 months of taking finasteride may point to a need for further testing for prostate cancer.
• PSA levels above 2 ng/mL during finasteride treatment may point to a need for further testing for prostate cancer.

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.

References

Citations

1. Nickel JC (2007). Inflammatory conditions of the male genitourinary tract: Prostatitis and related conditions, orchitis, and epididymitis. In AJ Wein et al., eds., Campbell-Walsh Urology, 9th ed., vol. 1, pp. 304–329. Philadelphia: Saunders Elsevier.