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In men with low testosterone, treatment may improve sexual functioning and quality of life but does not reduce fatigue

Diem SJ, Greer NL, MacDonald R, et al. Efficacy and Safety of Testosterone Treatment in Men: An Evidence Report for a Clinical Practice Guideline by the American College of Physicians. Ann Intern Med. 2020;172:105-18.

Review question

In men who have low testosterone levels without a related medical condition, what are the benefits and harms of treatment with testosterone?


Some men have a condition called hypogonadism, where the body does not produce enough testosterone. Testosterone treatment is approved for men who have low testosterone levels due to conditions like disorders of the hypothalamus, pituitary gland, or testes. Often, men who have nonspecific symptoms like low energy, lower sexual function, or low serum testosterone levels are treated with testosterone.  This review looked at whether treatment with testosterone was helpful and safe in men who did not have a medical condition to explain low testosterone levels.

How the review was done

The researchers did a systematic review of studies available up to May 2019. They found 38 randomized controlled trials. The average age of the men in the studies was 66 years.

The key features of the studies were:

  • most men had low testosterone levels;
  • testosterone was given through the skin (transdermal) or by injection into a muscle (intramuscular) and compared with placebo or no testosterone; and
  • most trials followed up men for less than 12 months.

What the researchers found

Compared with placebo, treatment with testosterone

  • improved sexual function, erectile function, and quality of life by a small amount;
  • did not improve physical function or reduce fatigue; and
  • did not increase risk for cardiovascular or serious adverse events, or prostate cancer (studies excluded men who had a history of heart disease, stroke, or prostate cancer).


In men who have low testosterone levels without a related medical condition, testosterone treatment may improve sexual function and quality of life but does not reduce fatigue.

Testosterone treatment vs placebo in adult men with low testosterone levels without a related medical condition


Number of trials (and men)

Effect of testosterone

Overall sexual function

7 trials (1140 men)

Improved sexual function measures by a small amount*

Erectile function

7 trials (1299 men)

Improved erectile function measures by a small amount*

Physical function

5 trials (1029 men)

No difference in effect

Vitality or fatigue

3 trials (665 men)

No difference in effect

Quality of life

7 trials (1043 men)

Improved quality of life measures by a small amount*

Adverse cardiovascular events†

14 trials (2415 men)

No difference in effect

Serious adverse events

8 trials (2268 men)

No difference in effect

Prostate cancer‡

10 trials (2143 men)

No difference in effect

*Amount of improvement was small (standardized mean difference between groups was ≥0.27 and <0.35 on different measurement scales).

†Most trials did not include men with a history of heart disease or stroke.

‡Most trials did not include men who had a history of prostate cancer or a high prostate specific antigen level.

Related Topics


A harmless, inactive, and simulated treatment.
Randomized controlled trials
Studies where people are assigned to one of the treatments purely by chance.
Systematic review
A comprehensive evaluation of the available research evidence on a particular topic.
The body's network of blood vessels. It includes the arteries, veins, and capillaries that carry blood to and from the heart.

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