Testosterone: High or Low, What’s the Big Deal?

Have you seen the TV commercials for testosterone boosters? They’ll make you think these over-the-counter products will have your muscles bulging and your sex drive humming. Some commercials say that the supplements will help you become “the man you used to be.”

But you’d be hard-pressed to find a urologist recommending these gimmicky, untested products. Still, testosterone is important to a man’s health, says UNC Health urologist Marc J. Rogers, MD. Here’s the real deal about why, and what to do if you’re concerned about low testosterone.

What Testosterone Does in the Body

Testosterone is the male sex hormone. It’s responsible for facial hair, muscle mass, growth of the penis and testicles, and sex drive. It helps the testicles produce sperm and the penis to become erect.

Around age 12 or 13, the pituitary gland signals the testicles to start producing testosterone. Testosterone production may start to ebb around age 50, but the clinical data is inconclusive, says Dr. Rogers.

Maintaining normal testosterone levels throughout a man’s life can support his sex drive and fertility, and build the strength of his muscles and bones.

Testosterone Levels: What They Mean

The most common symptoms of low testosterone are low libido (sex drive), erectile dysfunction, decreased energy levels, decreased muscle mass and brain fog, characterized by a lack of focus and mental clarity, Dr. Rogers says. The American Urological Association estimates that 20 to 50 percent of men have testosterone deficiency.

However, these symptoms are often caused by other things, including poor sleep habits, sleep apnea, diabetes, cardiovascular disease, obesity, and depression or anxiety, he says.

Your doctor will help you decide if measuring your testosterone levels is important. Blood tests are the only way to know for certain if testosterone levels are low. The normal range is above 300 nanograms per deciliter (ng/dL). Two blood tests on separate days must show low testosterone levels before a diagnosis is confirmed.

If a man’s testosterone is below 300 ng/dL, his doctor may prescribe testosterone replacement therapy.

“If a doctor prescribes testosterone replacement therapy and the patient’s levels normalize, but their symptoms don’t improve, then there’s likely another cause,” he says.

How to Treat Symptoms Associated with Low Testosterone

First, make sure you are sleeping well. Get treatment for sleep apnea, try to get diabetes and high blood pressure under control, and try to lose weight if you are obese. Moderate exercise is also helpful.

If these steps don’t control symptoms associated with low testosterone, then your doctor may prescribe testosterone replacement medicines. These are available only by prescription, so beware of ads or offers of testosterone supplements available over the counter or through the mail.

“These ‘testosterone boosters’ are not FDA regulated,” he says, “so it’s tough to gauge whether the ingredients listed on the label are really in the bottle.”

If you and your doctor determine that you need testosterone replacement therapy, the medicine comes in different forms, including:

  • A topical gel, applied daily on the shoulders
  • Injections men can give themselves daily at home in a leg muscle
  • Nasal sprays, taken two or three times a day
  • Tablets taken by mouth twice a day
  • Pellets inserted by a doctor into fat tissue every three months
  • Injections given by a clinician every 10 weeks

Pellets and long-lasting injections may provide more stable testosterone levels over the long term, Dr. Rogers says, and can be more convenient than daily self-treatments.

Alternatively, your doctor may prescribe a medicine (clomiphene citrate) that increases hormones produced by the pituitary gland, which stimulate testosterone production in the testicles.

Who Should Not Get Testosterone Replacement?

While testosterone is necessary for producing sperm, Dr. Rogers says, external testosterone replacement will lower sperm counts.

“It is not accurate that testosterone replacement will improve fertility issues,” he says. Talk to your urologist about how to identify and treat male fertility problems.

Talk to Your Doctor About Testosterone Levels

“Men should see their primary care physicians every year to check blood pressure, cholesterol levels, diabetes risks and other general health indicators,” he says. “Testosterone levels are not a standard part of that workup panel. It’s only checked if the person has symptoms.”

Erectile dysfunction and loss of muscle mass can prompt a testosterone blood test. A primary care physician may refer a patient to a specialist, such as a urologist or endocrinologist, for testing and treatment.

“Men of all ages can experience symptoms of low testosterone,” Dr. Rogers says. “It’s not just men over 50. It can be low at age 25, too.”

Also, some boys who are delayed entering puberty (after age 14) may also benefit from testosterone injections. First, other problems, including isolated gonadotropin deficiency (a lifelong deficiency of certain puberty hormones), should be ruled out.

If you are having symptoms of low testosterone, talk to your doctor or find one near you.