Frequently Asked Questions about Testosterone Therapy

Health Writer

Testosterone is a naturally occurring hormone in your body. Both men and women have testosterone, however, men's levels are generally much higher. In men, testosterone is produced in the testes. It is responsible for or contributes to the growth of male sex organs, development of facial hair, muscle mass, strength, fat distribution, sex drive, sexual function, bone strength and mood/energy levels. Testosterone therapy has become a popular medical treatment, with millions of men in the United States receiving some form of supplemental testosterone.

What are the symptoms of low testosterone?

The symptoms of low testosterone can vary, depending on the age when it occurs. Some of the symptoms include:

  • Infertility
  • Decrease in amount of semen during ejaculation
  • Decrease in sexual desire
  • Fatigue or low energy
  • Decrease in sexual function
  • Erectile dysfunction
  • Hair loss
  • Decreased muscle mass
  • Osteoporosis

What is a "normal" testosterone level?

There is much debate as to what a "normal" testosterone level is, however, the National Institutes of Health indicate that readings between 300 and 1,000 ng/dL would be considered normal. These levels are not broken down by age, therefore, normal for an 80 year old man and a 30 year old man might vary. In addition, laboratories might use different measurements, causing a variance in what is considered a normal or average range. Typically, low testosterone is considered less than 300 nanograms per deciliter.

How is low testosterone measured?

Testosterone levels are measured with a blood test.Testosterone levels tend to be highest during the morning hours, therefore it is recommended that the blood test is done between 7:00 A.M. and 10:00 A.M.  Because testosterone levels naturally fluctuate, some doctors request that two tests be done on separate days to get more accurate results.

What are the benefits of testosterone therapy?

If you have low testosterone levels (often called "low T"), receiving supplemental testosterone will raise the levels to within normal ranges. This can help increase muscle mass, reduce body fat and increase bone density. Some studies have shown testosterone therapy can help with weight loss.

While erectile dysfunction (ED) can sometimes be caused by low T, there are many other reasons for ED. Testosterone therapy should help with ED if it has been caused by low T. If not, other medical conditions might be the cause of ED. Increasing your testosterone levels should increase sexual desire.

Low testosterone levels can also cause lack of energy and fatigue. It might be responsible for depression or mood swings. Increasing levels may improve mood, self-esteem and energy levels.

What are the risks of testosterone therapy?

Some studies have shown that testosterone therapy can increase the risk of heart problems, especially in those who already have a heart condition. One study showed a 20 percent increase in heart attacks in those who have a heart condition. Other studies have shown an increase in prostate cancer, however, other studies have not found the same results. Overall, the long-term risks of testosterone therapy have not been well studied.

Some of the other side effects of testosterone therapy include:

  • Sleep apnea
  • Acne
  • Enlarged breasts
  • Decreased sperm production

For those considering this type of treatment, it is essential to talk to your doctor about both the risks and benefits of the treatment.


"New Study Adds Caution to Testosterone Therapy for 'Low T' " 2014, Jan 31, Patrick J. Skerrett, Harvard Health

"Testosterone Replacement Therapy," Date Unknown, Staff Writer, Cleveland Clinic

"Testosterone Therapy for 'Low T' Carries Risk: Endocrinologists," 2014, Feb 20, Kathleen Raven, Reuters News