The Reality Behind the Possible Side Effects

For men with confirmed testosterone deficiency, testosterone replacement therapy (TRT) may improve symptoms such as low energy, reduced libido, low mood and changes in body composition.

TRT can cause side effects, although not everyone will experience them. Some are more likely when treatment is first started, after a change in dose, or if testosterone levels become higher than intended. In many cases, reviewing the dose or treatment schedule is enough to improve things.

Fertility

TRT suppresses the normal hormonal signals from the brain to the testes. This can significantly reduce sperm production and, in some men, may temporarily stop sperm production altogether.

Anyone who may want children in the future should discuss this before starting treatment. Fertility plans can affect which approach is most appropriate and, in some cases, other options may need to be considered.

Raised haematocrit

One of the things we monitor during TRT is haematocrit — the proportion of the blood made up of red blood cells.

Testosterone stimulates red blood cell production and, in some men, the haematocrit gradually rises during treatment. Most people will not notice this happening, although occasionally headaches, facial flushing or breathlessness can occur.

If the haematocrit becomes significantly elevated, it may be associated with an increased risk of cardiovascular or thrombotic problems, which is why regular blood tests are important.

If it does rise too high, we would usually look at the testosterone dose and how the treatment is being given, as well as any other factors that might be contributing. Occasionally therapeutic venesection may also be considered where clinically appropriate.

Oestrogen and breast symptoms

Some testosterone is naturally converted into oestrogen. This is a normal process and men need oestrogen too, including for bone and sexual health.

Changes in hormone levels can occasionally lead to breast tenderness or swelling. Some men may develop gynaecomastia, where a small amount of breast tissue develops behind the nipple.

If this happens, the first step is usually to look at the overall testosterone treatment rather than simply focusing on the oestrogen result itself. Body weight, alcohol intake and other factors may also be relevant.

Oily skin and acne

Oilier skin and acne can occur during TRT, particularly during the first few months, after dose changes, or in men who have been prone to acne in the past.

Testosterone can increase activity in the sebaceous glands of the skin. Mild symptoms may settle with appropriate skincare and by making sure testosterone levels are not running higher than intended.

More troublesome or persistent acne may need assessment and treatment through a GP or dermatologist.

Mood changes

Changes in mood and wellbeing can sometimes occur during treatment.

Some men notice increased irritability or feel more emotionally reactive, particularly if testosterone levels become too high or vary significantly between doses. If that happens, it is worth reviewing the treatment and hormone levels rather than assuming it is simply something that has to be tolerated.

The key point

TRT is not suitable for everyone, and the potential benefits and risks need to be considered for each individual.

For men with confirmed testosterone deficiency who are properly assessed and monitored, treatment is generally well tolerated. Regular follow-up and blood tests allow changes such as raised haematocrit, altered hormone levels or other side effects to be picked up and dealt with.

Treatment may also need adjusting over time as symptoms, blood results or wider health change.

Common Myths and Questions About TRT Side Effects

Does TRT increase the risk of prostate cancer?

Current evidence is reassuring and does not show that TRT causes prostate cancer in men without pre-existing disease.

Testosterone can, however, affect the prostate and may cause a modest rise in PSA. PSA is therefore monitored where appropriate, taking into account age, symptoms, family history and other individual risk factors.

The purpose of monitoring is to identify any unexpected changes that may need further investigation, rather than because prostate cancer is an expected consequence of TRT.

Does TRT cause hair loss?

TRT does not cause male pattern hair loss in every man.

Testosterone can be converted into dihydrotestosterone, or DHT, which plays an important role in male pattern hair loss. Genetics are still the main factor determining who is likely to lose their hair.

If someone is already genetically prone to male pattern baldness, increasing testosterone levels may speed up hair loss, although this varies considerably from person to person.

Are side effects common on TRT?

Not everyone taking TRT will experience side effects.

Skin changes such as oily skin or acne can occur. Other issues, such as a rise in haematocrit or breast symptoms, are less common but are among the reasons regular blood tests and clinical reviews are part of treatment.

The aim is to pick up any problems early and adjust treatment where needed, rather than simply trying to achieve the highest possible testosterone level.

If you are taking TRT and develop new symptoms or are concerned about a possible side effect, speak to the doctor responsible for your treatment before making any changes yourself.

References

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