The hormone testosterone plays a big part in men's health, but perhaps its most meaningful role is to fuel sex drive and performance.
Testosterone levels tend to decrease with age. They peak by early adulthood and then can drop by up to 1% per year beginning around age 40. Sometimes an abrupt fall occurs because of an injury or illness (such as an infection), chemotherapy or radiation treatment, or certain medications.
When testosterone levels drop too low, men can experience a lackluster libido and erectile dysfunction (ED). Low levels can also contribute to fatigue, mood changes, reduced muscle mass, and loss of bone strength.
Most men can still maintain adequate levels of testosterone well into their later years. Staying healthy also helps slow the decline. Still, many older men consider testosterone replacement therapy (TRT) as a means to boost depleted levels. It's natural to think that TRT could make a man feel younger and add zest to his sex life.
But is it that simple? Can TRT really help? The short answer is maybe, but only in a specific way.
Good for sex
First of all, men need to realize that TRT won't turn back time, says Dr. Shehzad Basaria, associate director of the Section of Men's Health, Aging and Metabolism at Harvard-affiliated Brigham and Women's Hospital.
"Although quite a few studies in older men have shown that TRT improves muscle mass and strength compared with a placebo, this increase has not translated into improved physical function," he says. "Furthermore, large clinical trials have not shown that TRT improves vitality or memory."
On the other hand, research has shown that TRT can improve overall sexual activity and sexual desire in older men whose blood testosterone levels are clearly low.
But even this effect has its limits. A 2017 meta-analysis published in Current Opinion in Urology found that TRT improved libido and erectile dysfunction in men who have both low testosterone levels and mild ED. TRT was especially helpful for men who do not respond to ED drugs like sildenafil (Viagra), vardenafil (Levitra), and tadalafil (Cialis).
However, the researchers added that TRT might not help men with moderate or severe ED. In these cases, low testosterone is often not the cause of their ED, and other treatments like ED drugs are more effective.
Are you a candidate?
Speak with your doctor if you are concerned about low testosterone and its effect on your sex life. A review of symptoms and at least two early-morning blood tests to measure testosterone can confirm a diagnosis. (The normal range of blood testosterone is 300 to 1,000 nanograms per deciliter.)
There are several ways to receive TRT if it's prescribed: injections, patches applied nightly, or daily gels spread over your upper arms, shoulders, or thighs.
Traditionally, injected testosterone is given into a large muscle once every week or two. Injections done less often can result in a high testosterone level right after the injection that falls noticeably a few days prior to the next shot. This can cause a roller-coaster effect on mood, energy, and sex drive.
The newest option is a device that injects testosterone under the skin (similar to insulin shots) each week. This method is often more expensive than the regular muscle injections.
Keep in mind that even if you have low testosterone and multiple symptoms, TRT might not be the first recommendation by your doctor.
For instance, losing excess weight increases your own testosterone production. Also, switching certain medications may raise levels. These changes alone sometimes help relieve symptoms.
Consider possible health risks
Testosterone replacement therapy (TRT) may pose some health risks, and you should discuss them with your doctor. For instance:
Erythrocytosis. Erythrocytosis is a condition where the body makes too many red blood cells, which can increase the risk of stroke and heart attack.
Heart attack. A study in the September 2019 issue of The American Journal of Medicine found that men ages 45 and older with low testosterone who took TRT had a 21% greater risk of heart attacks and strokes (even without erythrocytosis) within the first two years of use compared with non-TRT users. Results from large clinical trials are still needed.
Prostate cancer. The link between TRT and a higher risk of prostate cancer is not clear. However, a study published online June 22, 2018, by PLOS One found no connection between TRT and aggressive prostate cancer among more than 58,000 men ages 40 to 89. But again, more research is needed.
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