Occasionally men experience low testosterone levels which can be due to a variety of causes. (See Testes Overview) Low testosterone levels can have clinical consequences involving poor sexual function, not feeling well and adverse changes in body composition. Such changes can include reduced muscle mass, increased fat mass and reduced bone mineral density and strength. As well, testosterone deficiency affects how you feel, concentrate and calculate. Restoration of normal testosterone levels is possible only after making a proper diagnosis and identifying contributing factors which may be treated.
Treatment for low testosterone levels has made significant advances in the past few years. There are no safe oral testosterone replacements but there are safe ways to give back testosterone to restore normal blood levels. There are several ways to give treatment; an injection, a transdermal patch or spreadable gel that delivers testosterone. It is important to note that treatment with testosterone must be monitored with periodic blood tests. This is necessary because too much testosterone can have adverse clinical consequences such as too much sexual desire, elevations in red blood cells (polycythemia), enlargement of the prostate or stimulation of a prostate cancer.
Testosterone replacement therapy has several important benefits:
It may or may not restore normal sexual desire/function but usually improves both libido and erections. Some men, however, become infertile by using testosterone because it may shut down FSH and LH which regulate sperm formation and maturation. Many men remain fertile and this issue should be addressed in every patient who is deficient in testosterone. Rarely, men feel too much libido which may be adverse in a relationship and needs to be discussed in every relationship.
Most men feel better on testosterone replacement therapy. Studies in on replacement therapy show an improvement in the sense of well-being or happiness. In addition, other cognitive function improves, such as better concentration and calculation. Most men also feel stronger, more confident, but sometimes too aggressive. All of these issues and concerns need to be discussed with the patient and their partner prior to the start of testosterone therapy so that each is aware of possible changes in their sexual relationship.
There are also several important risks of testosterone replacement therapy:
Red blood cell production is partially controlled by testosterone. Too little testosterone is associated with anemia and testosterone replacement can rarely cause too many red blood cells (polycythemia). Polycythemia can be associated with a decrease in blood flow to organs such as the brain resulting in a loss of brain function and even stroke. Therefore, it is important to monitor red blood cells periodically with a complete blood count at least yearly while on therapy.
Testosterone causes the growth of tissues which are sensitive to this hormone such as the prostate. Testosterone causes prostate growth and development in all men. Rarely, the testosterone therapy makes the prostate grow too much and causes benign prostate hyperplasia (BPH). BPH is a condition that causes symptoms of frequent nighttime urination and may lead to incomplete emptying of the bladder which can be the cause of the urge to urinate several times in row, dribbling or “forked” urinary stream. If this does happen, notify your doctor immediately to discuss this uncommon side effect. Usually this will necessitate discontinuance of testosterone. However, in extreme cases, another medication or even surgery may be necessary to stop the symptoms. This is the reason that a prostate exam be done at least yearly.
There is no clinical evidence that testosterone replacement therapy causes prostate cancer, but the therapy may make prostate cancer grow. Prostate cancer is common in men – approximately 1 in 6 men get prostate cancer. Prostate cancer screening is essential in all men and needs to monitored in every man on testosterone therapy. Typically men need a rectal exam and PSA done three months after starting therapy and at least yearly or even more often if the exam or the PSA changes while on therapy.
There are several ways that physicians can safely replace testosterone in male patients who need it.
Testosterone Injections (Depotestosterone)
An injection of testosterone is the oldest and least expensive form of testosterone replacement therapy. This is an intramuscular injection given by a nurse or can be taught to be given by a spouse or significant other. The injection is typically given every 10 to 14 days to maintain an adequate blood level of testosterone. Some men prefer this therapy because it does not require daily administration and some men dislike it because of the injections. The therapy can have peaks and valleys, typically a peak blood level occurs 2-4 days after the injection and a valley occurs before the next injection. The peaks and valleys can be minimized by changing the frequency of injections, the dose of testosterone or both. The therapy is monitored by blood levels of testosterone to achieve the best blood level while minimizing any side effects.
Testosterone Patches (Androderm)
Patches of testosterone can be applied to the skin daily, much like a Band-Aid which is a delivery system that can work well in some men. Patches produce a smooth, even blood level of testosterone but about 40% of men have difficulty with the adhesion of the patch to the skin and 40% develop a rash from the patch materials.
Testosterone Gel (Androgel, Testim)
The most common form of testosterone replacement is by daily administration of a gel which you rub into the skin. It also delivers a smooth, even blood level of testosterone which typically has no major skin irritation. Care must be taken to avoid contact of others to the skin area where the gel is applied.