Hormone replacement therapy

The goal of hormone replacement is to improve quality of life, sense of well-being, sexual function, muscle strength, and bone mineral density.

Replacement of the hormone testosterone aims to restore levels in men diagnosed with low testosterone caused by problems in the testicles (primary hypogonadism).

Pituitary hormones may be replaced if low levels are caused by a problem in the pituitary gland (secondary hypogonadism). These hormones can stimulate genital development in boys. They can increase sperm production and restore fertility in men.

Risks of testosterone treatment

In addition to side effects, hormone replacement carries some risks related to natural changes in hormone levels. Testosterone replacement can cause both cancerous and non-cancerous prostate tumours, enlarged breasts, infertility, and blood clots in the veins.

Do not use testosterone replacement therapy if you have:

  • Heart problems
  • Prostate cancer
  • An enlarged prostate that causes problems urinating
  • Male breast cancer
  • A high red blood cell count
  • Severe sleep apnoea
  • Infertility but might want to have children

Types of testosterone replacement therapy

Different types of testosterone replacement are absorbed into the body differently and have different side effects. Consider starting therapy with a type that can be stopped easily (short-acting treatment) if side effects are a problem. Not all types of testosterone replacement therapy are available in all countries. Work with your doctor to choose the right type of testosterone replacement therapy for you.

Types of testosterone replacement therapy



Side effects

Taken by mouth

Short-acting: testosterone undecanoate pills, sublingual testosterone (tablet placed under the tongue to dissolve) buccal testosterone tablet (swallowed)Widely used with few or no side effects. Safe when used for a limited time.

Injected into the buttock or arm

Short-acting: testosterone cypionate and enanthate (every 2–3 weeks).
Long-acting: testosterone undecanoate
(every 3 months), subdermal depot (patch placed under the skin releases medicine over 5–7 months)
Short-acting injections can cause testosterone levels to vary, sometimes too high and sometimes too low. This may cause symptoms to appear and disappear during treatment.

Applied to skin

Short-acting: transdermal testosterone patch or gel

Long-acting: subdermal depot (patch injected under the skin releases medicine over 5–7 months)

Short-acting treatment can cause skin to become irritated. Medicine can be transferred accidentally to another person who comes into contact with it.
Long-acting treatment can cause skin infection. The implanted patch has a 10% chance of coming out unexpectedly.