Testosterone, the primary hormone produced by the testicle, promotes most of
the masculine characteristics of the body. These �secondary sexual
characteristics� include development of the penis, increased muscle strength and
mass, facial and body hair and male sexual function. There are many medical
conditions in men that result in low testosterone levels, a condition known as
hypogonadism. Hypogonadism can cause symptoms such as loss of energy,
depression, thinning of the bone (osteoporosis), loss of sexual interest and
function and muscle wasting. Men are less likely than women to be evaluated for
osteoporosis. Osteoporosis increases the risk of hip fracture which has a
mortality rate of 30% during the first year. For that reason screening for low
testosterone and associated osteoporosis before a fracture occurs can result in
life saving treatment.
Trauma to the testicles such as sports injuries or mumps, tumors of the
pituitary gland or simply prolonged and severe illnesses can all cause low
testosterone levels. Testosterone levels in men typically decline with aging and
by the age of 60 about 20% of men have low testosterone levels. Hypogonadism
developing due to aging is sometimes called �andropause�. The first challenge
for those suffering from a low testosterone level is to have the condition
properly diagnosed since symptoms are non-specific and may be attributed to age
alone. Diagnosing low testosterone can usually be done with a simple blood test.
Doctors disagree about the best test to use for diagnosing low testosterone but
in general the total or free testosterone level (not bound to a carrier
substance in the blood) or both together, are the most frequently used.
Once a low testosterone level is detected and if there is no reversable cause
of this problem then testosterone replacement is generally advised. The use of
an injection to administer testosterone has been the most commonly used method
until the last decade or so. Testosterone containing patches and gels have been
developed that can be applied to the skin. The hormone is then absorbed through
the skin into the blood stream. Although testosterone can be taken by mouth this
method is not advised due to the risk of liver toxicity.
Among the first preparations designed for skin application was Testoderm
which employs a testosterone containing patch applied directly to the testicle.
Due to inconvenience and discomfort this product has not been very popular.
Another patch is Androderm which can be placed on any area of skin on the body
which is free of hair. The adhesive on the patch occasionally causes a skin
rash, and the patch itself is cumbersome. Up to one third of individuals using a
testosterone patch experience some discomfort.
Avoiding the inconvenience of a patch is Androgel which was approved by the
FDA in 1999. Testim is another testosterone gel product. The gel is rubbed
directly into the skin every day without the need for a patch. Many men find
this the easiest and least irritating of the transdermal preparations of
testosterone. Studies have shown high levels of patient satisfaction with gel
product. In a study conducted at Duke University researchers found that men with
testosterone levels less than 300 ng/dl treated with Androgel (testosterone gel)
had significant improvement in sexual function, muscle strength and lean body
mass. Overall satisfaction was better with Androgel than with the testosterone
patch.
Can testosterone gel be of benefit to women too? Some physicians have used
small amounts of testosterone gel applied to the clitoris and labia to improve
sex drive and orgasm in women with sexual dysfunction. Controlled studies of
testosterone gel used in this manner in women are currently not available
although some experts assert that testosterone is beneficial to a woman�s sexual
response.
There are several important precautions to follow when using testosterone
supplementation. Although testosterone probably does not cause cancer to develop
within the prostate, it will promote the growth of prostate cancers that
otherwise may have been indolent. For this reason PSA levels should be monitored
and the prostate examined regularly in testosterone users. Excessive amounts of
testosterone may cause breast enlargement (gynecomastia) due to the body�s
conversion of excess testosterone to estrogen. Aggressive behavior may be
promoted as well.
Testosterone is a controlled substance which can be obtained by prescription
from a licensed physician only. When used appropriately it can make a
substantial contribution to the well being of men with hypogonadism.
