Testosterone is a hormone produced by the testicles and is responsible for the proper development of male sexual characteristics. Testosterone is also important for maintaining muscle bulk, adequate levels of red blood cells, bone density, sense of well-being, and sexual and reproductive function.
Inadequate testosterone production is not a common cause of erectile dysfunction (ED). When ED does occur with decreased testosterone production, testosterone replacement therapy may improve the ED.
What causes testosterone deficiency?
As a man ages, the amount of testosterone in his body gradually declines. This natural decline starts after age 30 and continues throughout life. The significance of this decline is controversial and poorly understood. Among other potential causes of testosterone deficiency are:
- injury or infection to the testicles
- chemotherapy or radiation treatment for cancer
- genetic abnormalities such as Klinefelter’s Syndrome (extra x chromosome)
- hemochromatosis (too much iron in the body)
- dysfunction of the pituitary gland (a gland in the brain that produces many important hormones)
- medications, including hormone analogues used to treat prostate cancer and steroids
- chronic illness
- cirrhosis of the liver
- chronic renal (kidney) failure
- inflammatory disease such as sarcoidosis (a condition that causes inflammation of the lungs and other organs)
- congenital conditions, Kallman’s Syndrome (low hormones, inability to smell and other abnormalities)
What are the symptoms of testosterone deficiency?
Symptoms of testosterone deficiency include the following:
- decreased sex drive
- decreased sense of well-being
- depressed mood
- difficulties with concentration and memory
- erectile dysfunction
What are the changes that occur in the body with testosterone deficiency?
Changes that occur with testosterone deficiency include:
- a decrease in muscle mass, with an increase in body fat
- variable effects on cholesterol metabolism
- a decrease in hemoglobin and possibly mild anemia
- fragile bones (osteoporosis)
- a decrease in body hair
How do I find out if I have a testosterone deficiency?
The only accurate way to detect the condition is to have your doctor measure the amount of testosterone in your blood. It sometimes may take several measurements of testosterone to be sure if a patient has a deficiency, since levels of testosterone tend to fluctuate throughout the day. The highest levels of testosterone are generally in the morning. This is why doctors prefer, if possible, to obtain early morning levels of testosterone.
What options are available for testosterone replacement?
The options available for testosterone replacement are:
- intramuscular injections, generally every two or three weeks
- testosterone patches worn either on the body or on the scrotum (the sac that contains the testicles). These patches are used daily. The body patch application is rotated between the buttocks, arms, back or abdomen.
- testosterone gels that are applied daily to the shoulders, upper arms, or abdomen.
Each of these options provides adequate levels of hormone replacement. Each has side effects and advantages and disadvantages. Intramuscular injections produce wider swings in hormone concentration, with higher levels shortly after the injection and lower levels just before the next injection is due. They may also produce increases in blood cell count that are higher than normal.
The body patches may produce skin irritation in a significant number of men, requiring discontinuation of the patch. The gels require care in making sure that the hormone is not accidentally transferred to another person or partner.
There are currently no pills available in the United States that provide adequate levels of hormone replacement. In addition, oral medications may produce liver abnormalities and are to be avoided.
The choice of hormone replacement therapy is best made with a thorough discussion between a patient and his physician.
Who shouldn’t take testosterone replacement therapy?
Testosterone replacement therapy may stimulate growth of the prostate. If early prostate cancer is present, testosterone may stimulate the cancer’s growth. Therefore, men who have prostate cancer should not take testosterone replacement therapy. It is important for all men considering testosterone replacement therapy to undergo prostate screening before starting this therapy.
Although it is a rare condition, men who have breast cancer should not take testosterone replacement therapy.
What are the side effects of testosterone replacement therapy?
In general, hormone replacement therapy is safe. It is associated with some side effects, including:
- acne or oily skin
- mild fluid retention
- stimulation of prostate tissue, with perhaps some increased urination symptoms such as decreased stream or frequency
- breast enlargement
- worsening of sleep apnea (a sleep disorder that results in frequent night time awakenings and daytime sleepiness)
- decreased testicular size
Many of these side effects are not common.
Laboratory abnormalities that can occur with hormone replacement include:
- changes in cholesterol concentrations
- increase in red cell count
- decrease in sperm count, producing infertility (especially in younger men)
If you are taking hormone replacement therapy, regular follow-up appointments with your physician are important.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 8/3/2009...#10052