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Males may experience low testosterone as they get older or due to some health conditions. Symptoms can be subtle, but treatment may help if the symptoms affect your lifestyle.

Alternative names for low testosterone

People may also refer to low testosterone as:

  • low T
  • male menopause
  • andropause
  • testosterone deficiency
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Testosterone is a hormone that can affect appearance and sexual development, stimulate sperm production and sex drive, and help build muscle and bone mass. It is typically produced by the testicles in people assigned male at birth.

Who can have low testosterone?

While people assigned male at both and people assigned female at birth produce testosterone, this article focuses on symptoms of low testosterone in people who were assigned male at birth. Research suggests that some doctors may prescribe testosterone off-label to females to improve libido, but this use has not been approved by the Food and Drug Administration (FDA).

Though sex and gender exist on a spectrum, the studies and surveys below used the terms “male” and “men” and did not report data on, or include, participants who were transgender, nonbinary, gender nonconforming, genderqueer, agender, or genderless.

To maintain the specificity and accuracy of the research, this article will use the terms “male” and “men” throughout.

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Testosterone production typically decreases with age. According to the American Urological Association, about 40% of males ages 45 and older have low testosterone.

If your testosterone production drastically drops, you may experience a range of symptoms. Signs of low testosterone are often subtle and can include:

Low sex drive

Testosterone plays a key role in your sex drive or libido. Some people may experience a decline in sex drive as they get older, but those with low testosterone will likely experience a more drastic drop.

Difficulty achieving and maintaining an erection

Testosterone aids in achieving and maintaining an erection. It tells brain receptors to produce nitric oxide, which is a molecule that helps trigger a series of chemical reactions to produce an erection.

With low T, you may have difficulty achieving an erection before sex or having spontaneous erections, such as during sleep.

However, research is inconclusive on whether testosterone replacement therapy can successfully treat erectile dysfunction. A 2016 review of studies looked at this therapy in males with erection difficulties and nearly half showed no improvement.

Other health conditions can cause erectile difficulties. These include:

Smoking and alcohol use can also contribute.

Hot flashes

Hot flashes can be a sign of low testosterone. This can feel like a sudden sensation of warmth. You may also experience:

Hair loss

Testosterone plays a role in hair production. Balding is a natural part of growing older for many males, and while it can be hereditary, those with low testosterone may lose body and facial hair as well.


Males with low testosterone may report extreme fatigue and decreased energy. You may have low T if you’re consistently tired despite getting plenty of sleep or if you find it harder to get motivated to exercise.

Decreased muscle mass

A 2016 review found that testosterone affects muscle mass but not necessarily strength or function. Males with low T may notice a decrease in muscle mass.

Increased body fat

Low testosterone levels may cause increased body fat or gynecomastia, which is enlarged breast tissue. Gynecomastia can occur when there is an imbalance of testosterone and estrogen in the body.

Decreased bone mass

Osteoporosis is a condition that affects bone density. Testosterone helps produce and strengthen bone, so males with low testosterone, especially older men, may have lower bone volume and be more susceptible to bone fractures.

Mood changes

Males with low testosterone can experience mood changes. Since testosterone influences many of the body’s physical processes, it can also influence mood and mental capacity.


Both testosterone levels and cognitive functions, particularly memory, decline with age. As a result, doctors have theorized that lower testosterone levels could contribute to affected memory.

According to a 2019 review of studies, testosterone supplementation may improve memory in older men with low testosterone though the effect may be small.

However, a 2017 study on testosterone supplementation did not find memory improvements in 493 men with low testosterone levels who took testosterone or a placebo.

Smaller testicle and penis size

The body requires testosterone to develop the penis and testicles, so low testosterone levels could contribute to a disproportionately smaller penis or testicles. Other conditions and circumstances can cause a smaller penis and testicles, as well.

Low blood counts

Low testosterone may increase your risk for anemia, according to a 2017 study. When researchers administered testosterone gel to males with low testosterone and anemia, they saw improved blood counts compared to males who used a placebo. Blood counts also improved in males with known causes of anemia, like iron deficiency.

Testosterone levels naturally decrease as males get older, but other conditions or circumstances may also cause low testosterone. These may include:

Testosterone levels are typically 300 to 1,000 nanograms per deciliter (ng/dL). Low testosterone is when testosterone levels fall below 300 ng/dL. A blood test called a serum testosterone test can determine your testosterone level.

Other tests may be performed to determine the cause of low testosterone.

Tests to diagnose low testosterone and its causes include:

  • serum testosterone
  • luteinizing hormone
  • blood prolactin level

Testosterone replacement therapy is a common treatment for low testosterone.

If low testosterone symptoms are bothering you, you can talk with a doctor to determine if testosterone replacement therapy is right for you.

Testosterone replacement therapy is a lifelong treatment. If you stop treatment, your testosterone levels will drop.

Side effects can include:

  • acne
  • enlarged prostate
  • shrinking testicles
  • decreased sperm count
  • high red blood cell count
  • fluid retention
  • swollen feet or ankles

This therapy may not be right for you if you:

  • have an untreated heart condition
  • have breast or prostate cancer
  • have sleep apnea
  • have elevated red blood cell counts
  • plan to have children

Having low testosterone may increase your risk of developing other health conditions, which may require treatment.

What happens when a man’s testosterone is low?

Low testosterone in males can occur with aging or due to some health conditions. It can affect different body systems, resulting in symptoms that affect memory, mood, bone and muscle, sex drive, and the ability to get or maintain an erection.

What are the signs of low testosterone in males?

You may have low testosterone if you’re experiencing a reduction in your sex drive, difficulty achieving or maintaining an erection, hair loss, and fatigue. A doctor can conduct tests, such as a serum testosterone test, to diagnose low testosterone. They may also recommend additional tests to rule out other conditions.

Males experience a gradual decrease in testosterone as they get older. The older you are, the more likely that you’ll have low testosterone.

A variety of factors can cause low testosterone. A doctor can check your testosterone level with a simple blood test.

If you have low testosterone and the symptoms bother you, a doctor may recommend testosterone replacement therapy.

If you would like to know your testosterone levels, LetsGetChecked offers male hormone tests at home at various price points.

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