Examples
|
| Avodart | dutasteride |
| Proscar | finasteride |
How It Works
5-alpha reductase inhibitors interfere
with the effect of certain male hormones (androgens) on the prostate. This
slows the growth of the prostate and can even cause it to become smaller, which
may help improve the symptoms of
.
But
since prostate size does not always correspond to the severity of a man's
symptoms, these medicines will not give satisfactory results in every case.
When you stop taking the medicine, symptoms usually
return.
Why It Is Used
5-alpha reductase inhibitors are not
recommended for men who have BPH symptoms without a noticeably enlarged prostate.
5-alpha reductase inhibitors may be prescribed for men who have bothersome,
moderate symptoms of BPH.
How Well It Works
Most men who use 5-alpha reductase
inhibitors report about a 3-point decrease in their
American Urologic Association (AUA) symptom index.
This change represents a noticeable improvement in symptoms. 5-alpha reductase inhibitors also decrease the risk of
complications, such as being unable to urinate (urinary retention), and make it
less likely that you will need surgery.
It may take up to 6 to 12 months before symptom improvement is
noticeable.
Using a combination of an alpha-blocker with a
5-alpha reductase inhibitor may help your symptoms more than either medicine
alone.
Side Effects
5-alpha reductase inhibitors appear to be
very safe and well tolerated. Side effects found in the first year of use
included:
- Decreased sex drive.
- Increased
ejaculatory dysfunction (such as a smaller amount of semen
ejaculated).
- Difficulty getting an erection.
- Breast
tenderness or enlargement.
These side effects may go away after a year or more of taking the medicine.
See Drug Reference for a full list of side effects. (Drug Reference is
not available in all systems.)
What To Think About
5-alpha reductase inhibitors
reduce the size of the prostate. But since a reduction in size does not always
bring about symptom relief, these medicines will not give satisfactory results
in every case. When you stop taking the medicine, symptoms usually
return.
5-alpha reductase inhibitors lower prostate-specific
antigen (PSA) levels. Because PSA levels are used to detect early-stage
prostate cancer, men interested in taking a 5-alpha reductase inhibitor might
consider the following:
- Most experts suggest that men be checked for
the presence of prostate cancer (using the PSA test and a digital rectal exam)
before taking 5-alpha reductase inhibitors.
- Follow-up PSA levels
that have not decreased by approximately 50% after 6 months of taking a 5-alpha
reductase inhibitor may indicate a need for further testing for prostate
cancer.
- PSA levels above 2 ng/mL (nanograms per milliliter) during
5-alpha reductase inhibitor treatment may indicate a need for further testing
for prostate cancer.