Before starting TRT, it’s important to know the potential risks of testosterone therapy.

Testosterone should not be used in men with breast cancer or known or suspected prostate cancer.

Patients with severe unstable heart disease, severe liver disease or severe kidney disease are not recommended to use testosterone supplements unless under close medical supervision.

Before initiating TRT, your doctor should check for prostate abnormalities by means of a digital rectal examination and a blood test for Prostate Specific Antigen (PSA).

These tests will ensure complications of the prostate should not arise from testosterone usage.

Side effects can occur if testosterone is used in excessive quantities. These may include:
• Too frequent or persistent erections of the penis (priapism)
• Nausea and vomiting
• Swelling of the ankles
• Acne
• Headache
• Gynaecomastia (breast development)
• Increased appetite

These effects are usually associated with excessive levels of serum testosterone from an incorrect dose. Due to their mode of administration, testosterone gels and creams generally keep testosterone blood levels within the normal therapeutic range for men and therefore side effects are unlikely to occur.


Prostate Disease

A. Benign prostatic hyperplasia (enlarged prostate): The use of testosterone will increase the size of the prostate, mainly during the first six months of treatment. Men with testosterone deficiency often have reduced prostate size and most increases in prostate size result in a return to “normal” prostate volume.

Many medical studies have failed to show any deterioration in obstructive symptoms attributable to benign prostatic hyperplasia during treatment with testosterone. Urinary retention has not been reported at rates higher than in control subjects.

B. Prostate cancer: One of the biggest myths in men’s health today is testosterone treatment increases the risk of developing prostate cancer. Whilst lowering of testosterone levels is a standard treatment for metastatic prostate cancer, there is no evidence to suggest replacement of low testosterone levels into the normal range leads to any increase in the occurrence of the disease. Numerous medical studies unequivocally show there is no significant increase in the occurrence of prostate cancer and a variable increase in the levels of prostate specific antigen (PSA). The authors of one paper concluded, “there is no compelling evidence that testosterone has a causative role in prostate cancer… (nor) increases the risk”. As part of the routine monitoring of testosterone replacement therapy, regular digital rectal examination and measurement of PSA are recommended.

Moreover, the evidence is becoming clear that men with low testosterone are more likely to develop prostate cancer; and testosterone plays a protective role on the prostate.
Adverse Changes in Serum Lipids

Synthetic testosterone derivatives are associated with adverse changes in serum lipids. However, the use of pure testosterone (e.g., testosterone implants, patches, creams and gels) is not associated with any changes to cholesterol or serum lipid concentrations. There is no known interaction between testosterone and lipid lowering medications.

testosterone old couple
Coronary Heart Disease

A major theoretical concern regarding testosterone administration is the possibility it could increase the risk of cardiovascular disease.

Such a concept is based on the higher incidence of cardiovascular events in men than in women. However, this may be much more readily explicable by the protective effects of oestrogen, a hormone found in much higher quantities in women. There is little data to support a causal relationship between high testosterone levels and heart disease. In fact, a significant body of evidence suggests the opposite may be true – men with low testosterone levels may be at higher cardiovascular risk. There are reports testosterone replacement can improve symptoms of chronic stable angina. There are direct observations showing vasodilation following intra- coronary injections of testosterone. There are no reports of increasing incidence of cardiovascular disease including myocardial infarction, stroke or angina in reports of testosterone replacement therapy.


Polycythaemia (an abnormal increase in red blood cells)

A well know side effect of chronic testosterone administration is the occurrence of polycythaemia, with a rise in haematocrit (the percentage of whole blood composed of red blood cells). This is particularly common when the intra-muscular route (injections) is used and high serum testosterone levels are present for some weeks following each injection. Interestingly, men with hypogonadism tend to have anaemia and reduced hematocrit concentrations. In these men, testosterone replacement leads to normalisation.

There is a direct relationship between testosterone dose and the incidence of polycythaemia. This effect, while not life threatening or severe, requires the need for regular monitoring (yearly) by a medical professional. If polycythaemia occurs, a reduction of the dose of testosterone is required and/or phlebotomy (drawing of blood) to reduce the red blood cell count and resolve the situation.

Long term risks with testosterone replacement therapy are minimal, particularly in regard to the major concerns addressed above. Side effects from excessive testosterone dosing are noted, but such adverse reactions are extremely unlikely with testosterone cream or gel topical administration.


Further Reading:

What is Testosterone?

Testosterone Deficiency – Causes and Diagnosis

Testosterone Replacement Therapy  (TRT)

Testosterone Online Self-Assessment Questionnaire

Testosterone for Men – Quick Q & A

The information in this article has been taken with permission from the official Lawley booklet on Understanding Testosterone in Men