Testosterone plays many roles in a man’s life. It aids sperm production, contributes to muscle building and strong bones, and puts hair on his chest and elsewhere on his body. It is also the primary male sex hormone.
As you get older, however, your testosterone level begins to decline slowly, by one percent per year approximately from age 30 onwards. Eventually, you may begin to experience symptoms of low testosterone. These include:
- Reduced sex drive (low libido)
- Erectile dysfunction
- Depressed mood and irritability
- Loss of muscle mass and strength
- Loss of body hair
- Osteoporosis, or weakened bones
- Gynecomastia, or development of breasts
- Increase in body fat
Low testosterone - the medical term is hypogonadism - can be caused by many factors besides age, such as obesity, poorly managed type 2 diabetes, sleep apnea, testicle injuries, Klinefelter syndrome (a genetic condition), and treatment for prostate cancer.
Fortunately, the treatment for low testosterone can help restore your libido and ease other symptoms. However, this treatment has side effects. But first, what defines low testosterone?
Testosterone levels at a glance
Normal testosterone levels fall between 300 and 1,000 nanograms per deciliter. However, testosterone levels fluctuate. Your doctor will require you to take more than one blood test to confirm your results before starting testosterone replacement therapy (TRT) for low testosterone.
What are the common types of TRT?
Many types of TRT exist, and your doctor will review the pros and cons of each to help determine which one will work best for you. Much of that decision will be based on your personal preferences. The types of TRT include:
These are self-administered every week. You can inject yourself in your abdomen or the muscles in your thighs or buttocks.
You may find these convenient because you only have to inject once per week. However, if you don’t like needles, you likely will want to consider a different method. Longer-lasting injections, administered at your doctor’s office, are also an option.
These are other ways to get testosterone into your bloodstream. They may not be as effective as injections, but as long as they raise your T level into the normal range and ease your symptoms, they are a good option. Unlike injections, they must be applied every day.
You’ll rub the gel into your shoulders, upper arms, thighs, or other areas of your body. Your doctor will tell you the most appropriate place for your TRT.
For example, one brand, Testim, must be applied only to your shoulders or upper arms. It is unsafe for children and women to touch testosterone gels, so be careful to cover up before contact.
These are applied to the skin once a day. They can be placed in several different areas of your body, such as your upper arms, thighs, and back.
However, they should be placed in a different spot each day. Don’t use the same spot more than once every seven days.
If you want a long-term, hands-off approach to TRT, these may be right for you. In a procedure that takes about 15 minutes, your doctor will place six to twelve small pellets just under your skin, often around your hip.
These pellets will deliver testosterone continuously over a three to four-month period. For some men, they may last as long as six months.
You will meet regularly with your doctor to determine if your TRT is working or whether you need to change your dose.
During your appointment, your doctor will take a blood sample to measure your testosterone level to determine if it has risen into the normal range. You also will discuss your symptoms. Your doctor will want to know, for example, whether your sex drive has improved. Another topic of discussion: side effects.
What are the possible side effects of TRT?
While TRT may help improve symptoms of low testosterone, it does come with some risks. For example, the FDA has required that TRT makers include a warning that notes an increased risk of heart attacks and strokes among men who take TRT.
Know the symptoms of heart attack and stroke and call 911 right away if you experience them.
Other possible side effects of TRT include:
- Acne, oily skin, or other skin irritation, particularly if you use testosterone gel
- Ankle swelling
- Breast development
- Increased red blood cell count, called polycythemia, which can boost your risk of blood clots. If you have a high red blood cell count before TRT, you should not be offered TRT.
- If you have sleep apnea, it may get worse on TRT. You should not start TRT until you have been treated for sleep apnea.
It’s important to know that taking TRT will stop your body from producing sperm. For men who do not plan to father children (or additional children), this likely is not a concern.
However, younger men with low testosterone should discuss this with their doctor before they begin TRT. If you discontinue TRT, your sperm production should resume, but it may take time. How long? That depends on how old you are and how long you have been taking TRT.
TRT and your prostate
TRT does not increase your risk of prostate cancer. However, if you already have prostate cancer, you and your doctor must weigh the potential risks.
Experts have long considered that testosterone functions as a fuel for prostate cancer growth and have recommended against TRT for men with prostate cancer.
However, new research has begun to challenge that notion. Taking the lowest dose of TRT needed to return your testosterone level to the normal range may be safe for some men with prostate cancer.
You should expect to be closely monitored to be sure your cancer does not get worse. You and your doctor should discuss the risks and benefits of TRT before you begin therapy.
Some experts recommend against offering TRT to men with an enlarged prostate that causes urinary difficulties. However, some recent research suggests that TRT does not make urinary symptoms worse; in fact, it may help relieve such symptoms.
Finally, keep in mind that TRT does not cure low testosterone. If you stop taking it, your testosterone level will drop again.
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AVEED (n.d.) product page
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Cleveland Clinic (2022). Testosterone skin gel
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