What are the side effects of testosterone replacement therapy?

Donna Hill Howes, RN
Family Practitioner

Side effects may include acne, flushing, shortness of breath, digestive tract problems, sleeping problems, mood swings, low sperm count, low ejaculation volume, enlarged prostate, and difficulty urinating. Some men may have breast enlargement and pain.

There are no studies that provide definitive conclusions regarding testosterone therapy and cardiovascular disease risk. Although numerous studies have suggested that testosterone therapy increases this risk, several recent studies do not support this conclusion. Some studies have shown that low testosterone is associated with increased cardiovascular risk. 

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All forms of testosterone replacement have risk associated. Side effects of testosterone replacement include:

  • Ankle swelling due to fluid retention
  • Worsening of sleep apnea (a potentially life-threatening problem, usually seen in overweight men with a snoring problem), also due to fluid retention
  • A thickening of the blood (polycythemia), which can increase the risk of blood clots
  • Quick prostate enlargement and problems emptying the bladder

Testosterone does not cause prostate cancer, but can make it grow faster. Testosterone can also cause infertility. Careful monitoring by a doctor is required once you start taking testosterone replacement to make sure that no significant side effects occur.

On the upside, the return of your sex drive, energy, concentration and physical strength are enormous benefits.

Always carefully weigh the risks and benefits to testosterone replacement.

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Side effects of testosterone replacement therapy can include the following:

  • acne
  • oily skin
  • small testicles
  • anger issues
  • heart attacks

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