More Slideshows from eMedicineHealth
Inflammatory Bowel Disease
What Is Testosterone?
Testosterone is a well-studied hormone, often related to muscular development and masculinity. Testosterone fuels the sex drive and adds muscle mass, and it also regulates moods and bone strength. If testosterone levels are below normal, a doctor may prescribe one of several types of treatments. However, there is debate about who needs to be treated.
Aging and Testosterone Levels
Testosterone levels decrease as males' age. Sometimes this lower level of testosterone is termed "andropause" or "male menopause" because for some men symptoms of irritable moods, decreased interest in sex, and hot flashes may develop. But for many men, decreasing levels of testosterone doesn't cause any of the above symptoms or problems.
Low Testosterone and the Body
In some men, low testosterone levels can cause changes that are noticeable or visible. These changes include less muscle mass (thinner muscles), loss of body hair, smaller testicles, softer testicles, and larger breasts.
Low Testosterone Affects Bones
Although osteoporosis (brittle bone disease) is usually thought of as occurring mainly in women, the disease in men is commonly caused by low testosterone. Low testosterone levels can cause bones to thin, weaken, and become more likely to fracture.
Low Testosterone and Sex
Low testosterone doesn't always interfere with sex, but it is possible. Some men with low testosterone may experience a drop in libido while others lose interest in sex completely. Low testosterone levels can make sex more difficult because it may be tougher to get or keep an erection.
Testosterone, Mood, and Thinking
Some of the changes that may occur with low testosterone are nonspecific symptoms such as easy irritability, mood changes, poor concentration, and feeling fatigued or having less energy. However, these nonspecific symptoms can be caused by other health problems such as anemia, sleep apnea, depression, or other chronic illnesses.
Low Testosterone and Infertility
One of the many functions of testosterone is to help produce sperm. When testosterone levels are low, the "sperm count" also can be low. If the sperm count is very low, the man may not be able to father a child.
What Causes Low Testosterone?
Although increased age is the most common cause of decreased testosterone levels in men, there can be other causes. Other common causes include:
- Diabetes (type 2)
- Kidney disease
- Liver disease
- Chronic obstructive pulmonary disease (COPD)
- Testicular injuries
- Pituitary gland problems
- Radiation therapy
- Steroid medications
Should You Be Tested?
You might need to be tested for low testosterone if you have erectile dysfunction (ED), a very low sex drive, low sperm count, loss of body hair, decrease of muscle mass, and a loss of height (due to bone problems such as osteoporosis).
Testing for Low Testosterone
Tests for testosterone levels are done by sampling the blood early in the morning when levels of testosterone are highest. Your doctor may want to run a second test a few days after running the first test to check for consistency in testosterone levels measured. Normal testosterone levels range from about 300 to 1000 ng/dL, although some labs consider 200 ng/dL the cutoff for low testosterone. Your doctor will help interpret the tests for you.
Treating Low Testosterone
If you are diagnosed with low testosterone, your primary care doctor may suggest you see a specialist such as a urologist or an endocrinologist. Not everyone with low testosterone will need or qualify for treatment. These specialists will help guide your treatment, and design an approach to your low testosterone problem that is best for you.
Testosterone Replacement Therapy
Low testosterone treatment is designed to boost testosterone levels. Studies suggest this increase in testosterone can strengthen muscles, protect bones, and improve sex drive. However, such treatments can have different effects from one man to another so it is difficult to predict the treatment outcomes for any one individual.
Treatment for low testosterone can be done by several different methods; intramuscular shots, topical gels and patches, oral tablets, and in a few individuals, implanted pellets have been used to deliver testosterone. Injections are the least expensive, but they can be painful. The shots are given about every 7 to 22 days, and testosterone levels can increase and then fall between shots.
Testosterone Gels or Patches
Gel or patch treatments for low testosterone are placed directly on the skin. The hormone seeps out of the patch or gel and goes through the skin, and is slowly absorbed into the blood. Gels and patches are applied every day, and as a result, the level of testosterone remains fairly steady. A drawback to these treatments is that they can cause itching, skin irritation, and blisters. In addition, women or children should not come in contact with skin that has been treated with a gel or patch to avoid absorbing any testosterone.
Testosterone tablets are placed on the gums above the incisors (teeth) about every 12 hours and slowly release testosterone. Gum tablets may cause a bitter taste, irritation to mouth tissues and gums, and may cause headaches. Fortunately, these side effects lessen over time. In addition the person can eat, drink, and kiss women and children while using testosterone tablets because they are not directly exposed to testosterone.
Risks of Testosterone Therapy
Although testosterone therapy has been tried in many individuals, the risks and benefits of this treatment over many years is still not known because such studies have not been completed. It is known, however, that drawbacks exist for testosterone treatment as some men may develop sleep apnea, an enlarged prostate, too many red blood cells, and acne. In some men, testosterone therapy may need to be stopped if the risks outweigh the benefits.
Testosterone Use and Cancer
Some researchers are concerned that long-term use of testosterone treatments may cause prostate cancer in older men. They advise that men taking testosterone need regular yearly checkups for early signs of prostate cancer. This is suggested for all men over 50, men over 40 with a family history of prostate cancer, and all African American men, as these groups are at higher risk for developing prostate cancer even without added testosterone treatments.
Who Should Not Take Testosterone?
As stated previously, some men shouldn't take testosterone treatments because they can aggravate symptoms or cause certain health conditions to worsen. Men who have prostate cancer, breast cancer, sleep apnea that is untreated, too many red blood cells (polycythemia), and poorly controlled heart disease should not take testosterone treatments.
More Reading on Low T