Journal of American
Medical Association (JAMA)
Evidence and Experience
the specialty of urology, 1998 was the year of
the penis. Last spring the field of urology was
taken by storm with the Food and Drug Administration's
(FDA's) approval of oral sildenafil citrate (Viagra)
forthe treatment of male erectile dysfunction.
The identification of nitric xide as a penile neurotransmitter1
paved the way for sildenafil, a selective cyclic
guanosine monophosphate (GMP)-specific phosphodiesterase
inhibitor that increases cyclic GMP levels, thus
enhancing the effect of nitric oxide in response
to sexual stimulation.
Benign prostatic hyperplasia
(BPH), the most common prostate disease, continues
to provide a source of controversy. Despite a previous
report3 questioning the short-term efficacy of
finasteride (Proscar) for obstructive voiding symptoms,
McConnell et al4 demonstrated that, when used for
4 years by symptomatic men with enlarged prostates,
finasteride caused a 2-fold decrease in the incidence
of urinary retention, a 2-fold decrease in the
need for prostate surgery, a mild decrease in urinary
symptoms, and a mild increase in urinary flow rates.
Finasteride caused occasional erectile dysfunction,
decreased libido, and decreased ejaculatory volume
but did not decrease the incidence of prostate
cancer. Yet despite these statistically significant
findings, most clinicians agree that the effectiveness
of finasteride for urinary obstruction is modest
and limited to men with palpably larger glands.
patient demand for alternative medicines for BPH
has created a huge market for herbal preparations,
most of which are ineffective or untested. The
most frequently used is an extract of the plant
Serenoa repens, known to patients as saw palmetto.
In a large systematic review of the published world
literature on saw palmetto, Wilt et al5 reported
that the herb does appear to have a mild salutary
effect on obstructive voiding symptoms. In randomized
placebo-controlled trials, men taking Saw Palmetto
were 1.7 (95% confidence interval [CI], 1.2-2.4)
times more likely to report overall improvement
in their urinary symptoms. Compared with placebo,
patients taking Saw Palmetto scored an average
of 3.5 points lower on the International Prostate
Symptom Scale (range, 0-35), 2.2 mL/s higher in
mean urinary flow rates, and 22 mL lower in postvoid
residual volumes. Nonetheless, the most important
message this year for men with BPH is that treatment
decisions should focus not only on symptoms but
also on the degree of bother and impact on
quality of life.
A Common Part of Aging
Why BPH Occurs
Saw Palmetto is used to treat
benign prostatic hyperplasia (BPH), an enlargement
of the prostate gland that affects about half of
all men older than fifty. BPH is a noncancerous
growth of the prostate gland. If the prostate grows
in mature men, it pinches the urethra, or urine
tube, and problems begin, including painful urination
and frequent nighttime trips to the bathroom. Researchers
estimate that BPH affects about ten million men
in the United States -- some in their forties,
half of all men older than fifty, and four out
of every five men older than eighty.
Research conducted in Europe
since the beginning of the 1980's shows that Saw
Palmetto reduced by nearly 50 percent the number
of times BPH sufferers had to get up to go to the
bathroom during the night and significantly reduced
painful, difficult urination. More recently, researchers
compared a saw palmetto extract with finasteride,
the conventional BPH drug. The study involved 1,098
men diagnosed with BPH, and researchers concluded
that both treatments relieved BPH symptoms in about
two-thirds of the men. But while the finasteride
reduced the prostate size it also decreased sex
drive and potency.
Saw Palmetto has become very
popular in the United States and it is the fifth
top-selling phytomedicine on the market, according
to a 1998 survey by Whole Foods magazine. In Europe,
medical doctors for years have prescribed Saw Palmetto
and other herbs to treat mild to moderate cases
of BPH. Today in Germany alone, the sale of BPH
products total 90 percent of sales which are using
Saw Palmetto as their number one source.
A Common Part of Aging
It is common for the prostate
gland to become enlarged as a man ages. Doctors
call the condition benign prostatic hyperplasia
(BPH), or benign prostatic hypertrophy.
|As a man matures,
the prostate goes through two main periods of growth.
The first occurs early in puberty, when the prostate
doubles in size. At around age 25, the gland begins
to grow again. This second growth phase often results,
years later, in BPH.
||Though the prostate
continues to grow during most of a man's life, the
enlargement doesn't usually cause problems until late
in life. BPH rarely causes symptoms before age 40,
but more than half of men in their sixties and as many
as 90 percent in their seventies and eighties have
some symptoms of BPH.
|As the prostate enlarges,
the layer of tissue surrounding it stops it from expanding,
causing the gland to press against the urethra like
a clamp on a garden hose. The bladder wall becomes
thicker and irritable. The bladder begins to contract
even when it contains small amounts of urine, causing
more frequent urination. Eventually, the bladder weakens
and loses the ability to empty itself. Urine remains
in the bladder. The narrowing of the urethra and partial
emptying of the bladder cause many of the problems
associated with BPH.
Many people feel uncomfortable talking about the
prostate, since the gland plays a role in both
sex and urination. Still, prostate enlargement
is as common a part of aging as gray hair. As life
expectancy rises, so does the occurrence of BPH.
In the United States alone, 375,000 hospital stays
each year involve a diagnosis of BPH.
It is not clear whether certain
groups face a greater risk of getting BPH. Studies
done over the years suggest that BPH occurs more
often among married men than single men and is
more common in the United States and Europe than
in other parts of the world. However, these findings
have been debated, and no definite information
on risk factors exists.
The cause of BPH is not well
understood. For centuries, it has been known that
BPH occurs mainly in older men and that it doesn't
develop in men whose testes were removed before
puberty. For this reason, some researchers believe
that factors related to aging and the testes may
spur the development of BPH.
Throughout their lives, men
produce both testosterone, an important male hormone,
and small amounts of estrogen, a female hormone.
As men age, the amount of active testosterone in
the blood decreases, leaving a higher proportion
of estrogen. Studies done with animals have suggested
that BPH may occur because the higher amount of
estrogen within the gland increases the activity
of substances that promote cell growth.
Another theory focuses on
dihydrotes-tosterone (DHT), a substance derived
from testosterone in the prostate, which may help
control its growth. Most animals lose their ability
to produce DHT as they age. However, some research
has indicated that even with a drop in the blood's
testosterone level, older men continue to produce
and accumulate high levels of DHT in the prostate.
This accumulation of DHT may encourage the growth
of cells. Scientists have also noted that men who
do not produce DHT do not develop BPH.
researchers suggest that BPH may develop as a
result of "instructions" given
to cells early in life. According to this theory,
BPH occurs because cells in one section of the
gland follow these instructions and "reawaken" later
in life. These "reawakened" cells then
deliver signals to other cells in the gland, instructing
them to grow or making them more sensitive to hormones
that influence growth.
Many symptoms of BPH stem
from obstruction of the urethra and gradual loss
of bladder function, which results in incomplete
emptying of the bladder. The symptoms of BPH vary,
but the most common ones involve changes or problems
with urination, such as
A hesitant, interrupted, weak
Urgency and leaking or dribbling.
More frequent urination, especially at night.
The size of the prostate
does not always determine how severe the obstruction
or the symptoms will be. Some men with greatly
enlarged glands have little obstruction and few
symptoms while others, whose glands are less enlarged,
have more blockage and greater problems.
Sometimes a man may not know
he has any obstruction until he suddenly finds
himself unable to urinate at all. This condition,
called acute urinary retention, may be triggered
by taking over-the-counter cold or allergy medicines.
Such medicines contain a decongestant drug, known
as a sympathomimetic. A potential side effect of
this drug may be to prevent the bladder opening
from relaxing and allowing urine to empty. When
partial obstruction is present, urinary retention
also can be brought on by alcohol, cold temperatures,
or a long period of immobility.
It is important to tell your
doctor about urinary problems such as those described
above. In 8 out of 10 cases, these symptoms suggest
BPH, but they also can signal other, more serious
conditions that require prompt treatment. These
conditions, including prostate cancer, can be ruled
out only by a doctor's exam.
Severe BPH can cause serious
problems over time. Urine retention and strain
on the bladder can lead to urinary tract infections,
bladder or kidney damage, bladder stones, and incontinence.
If the bladder is permanently damaged, treatment
for BPH may be ineffective. When BPH is found in
its earlier stages, there is a lower risk of developing
You may first notice symptoms
of BPH yourself, or your doctor may find that your
prostate is enlarged during a routine checkup.
When BPH is suspected, you may be referred to a
urologist, a doctor who specializes in problems
of the urinary tract and the male reproductive
system. Several tests help the doctor identify
the problem and decide whether surgery is needed.
The tests vary from patient to patient, but the
following are the most common.
Antigen (PSA) Blood
In order to rule out cancer as a cause of urinary symptoms, your doctor
may recommend a PSA blood test. PSA, a protein produced by prostate
cells, is frequently present at elevated levels in the blood of men
who have prostate cancer. The U.S. Food and Drug Administration has
approved a PSA test for use in conjunction with a digital rectal
exam to help detect prostate cancer in men age 50 or older and for
monitoring prostate cancer patients after treatment. However, much
remains unknown about the interpretation of PSA levels, the test's
ability to discriminate cancer from benign prostate conditions, and
the best course of action following a finding of elevated PSA.
Because many unanswered questions
surround the issue of PSA screening, the relative
magnitude of its potential risks and benefits is
unknown. Both PSA and ultrasound tests enhance
detection when added to DRE screening. But they
are known to have relatively high false-positive
rates, and they may identify a greater number of
medically insignificant tumors. Thus, PSA screening
might lead to treatment of unproven benefit that
could result in morbidity (including impotence
and incontinence) and mortality. It cannot be determined
from earlier studies whether PSA screening will
reduce prostate cancer mortality. Ongoing studies
are addressing this issue.
Urine Flow Study
doctor will ask a patient to urinate into a special
device which measures how quickly the urine is flowing.
A reduced flow often suggests BPH.
Men who have BPH with symptoms
usually need some kind of treatment at some time.
However, a number of recent studies have questioned
the need for early treatment when the gland is
just mildly enlarged. These studies report that
early treatment may not be needed because the symptoms
of BPH clear up without treatment in as many as
one-third of all mild cases. Instead of immediate
treatment, they suggest regular checkups to watch
for early problems. If the condition begins to
pose a danger to the patient's health or causes
a major inconvenience to him, treatment is usually
Since BPH may cause urinary
tract infections, a doctor will usually clear up
any infection with antibiotics before treating
the BPH itself. Although the need for treatment
is not usually urgent, doctors generally advise
going ahead with treatment once the problems become
bothersome or present a health risk.
The following section describes
the types of treatment that are most commonly used
Saw Palmetto 320mg
dosage daily to promote prostate health.
Over the years, researchers have tried to find a way to shrink or at
least stop the growth of the prostate without using surgery. Recently,
several new medications have been tested in clinical trials, and
the Food and Drug Administration (FDA) has approved four drugs to
treat BPH. These drugs may relieve common symptoms associated with
an enlarged prostate.
Finasteride (marketed under
the name Proscar), FDA-approved in 1992, inhibits
production of the hormone DHT, which is involved
with prostate enlargement. Its use can actually
shrink the prostate in some men.
Journal of American Medical
Saw Palmetto extracts
for treatment of benign prostatic hyperplasia:
a systematic review. Feb.
Wilt TJ, Ishani A, Stark G, MacDonald R, Lau J,
Department of Veterans Affairs
Coordinating Center of the Cochrane Collaborative
Review Group in Prostatic Diseases and Urologic
Malignancies, Minneapolis Veterans Affairs Medical
Center, Minn 55417, USA. firstname.lastname@example.org
OBJECTIVE: To conduct a systematic
review and, where possible, quantitative meta-analysis
of the existing evidence regarding the therapeutic
efficacy and safety of the Saw Palmetto plant extract,
Serenoa repens, in men with symptomatic benign
prostatic hperplasia (BPH). DATA SOURCES: Studies
were identified through the search of MEDLINE (1966-1997),
EMBASE, Phytodok, the Cochrane Library, bibliographies
of identified trials and review articles, and contact
with relevant authors and drug companies.
trials were included if participants had symptomatic
BPH, the intervention was a preparation of S repens
alone or in combination with other phytotherapeutic
agents, a control group received placebo or other
pharmacological therapies for BPH, and the treatment
duration was at least 30 days.
EXTRACTION: Two investigators
for each article (T.J.W., A.I., G.S., and R.M.)
independently extracted key data on design features,
subject characteristics, therapy allocation, and
outcomes of the studies.
SYNTHESIS: A total of 18 randomized controlled
trials involving 2939 men met inclusion criteria
and were analyzed. Many studies did not report
results in a method that permitted meta-analysis.
Treatment allocation concealment was adequate
in 9 studies; 16 were double-blinded. The mean
study duration was 9 weeks (range, 4-48 weeks).
As compared with men receiving placebo, men treated
with S repens had decreased urinary tract symptom
scores (weighted mean difference [WMD], -1.41
points [scale range, 0-19] [95% confidence interval
(CI), -2.52 to -0.30] [n = 1 study]), nocturia
(WMD, -0.76 times per evening [95% CI, -1.22
to -0.32] [n = 10 studies]), and improvement
in self-rating of urinary tract symptoms; risk
ratio for improvement (1.72 [95% CI, 1.21-2.44]
[n = 6 studies]), and peak urine flow (WMD, 1.93
mL/s [95% CI, 0.72-3.14] [n = 8 studies]). Compared
with men receiving finasteride, men treated with
S repens had similar improvements in urinary tract
symptom scores (WMD, 0.37 International Prostate
Symptom Score points [scale range, 0-35] [95% CI,
-0.45 to 1.19] [n = 2 studies]) and peak urine
flow (WMD, -0.74 mL/s [95% CI, -1.66 to 0.18] [n
= 2 studies]). Adverse effects due to S repens
were mild and infrequent; erectile dysfunction
was more frequent with finasteride (4.9%) than
with S repens (1.1%; P<.001). Withdrawal rates
in men assigned to placebo, S repens, or finasteride
were 7%, 9%, and 11%, respectively.
CONCLUSIONS: The existing
literature on S repens for treatment of BPH is
limited in terms of the short duration of studies
and variability in study design, use of phytotherapeutic
preparations, and reports of outcomes. However,
the evidence suggests that S repens improves urologic
symptoms and flow measures. Compared with finasteride,
S repens produces similar improvement in urinary
tract symptoms and urinary flow and was associated
with fewer adverse treatment events. Further research
is needed using standardized preparations of S
repens to determine its long-term effectiveness
and ability to prevent BPH complications.