Testosterone Replacement Therapy: Benefits, Risks & Side Effects

Testosterone replacement therapy (TRT) is a treatment used to correct testosterone levels that are below the normal range. Low testosterone can happen due to natural changes, such as andropause, or as a result of hypogonadism, chemotherapy, or radiation therapy.

The goal of testosterone replacement therapy is to relieve symptoms such as low libido, irritability, weight gain, and loss of muscle mass. This can help improve quality of life and overall well-being.

However, testosterone replacement therapy can cause side effects, including acne, mood changes, blood pressure changes, and possible cardiovascular risks. It should only be used under medical guidance after symptoms and blood tests confirm low testosterone.

When TRT is recommended

Testosterone replacement therapy may be recommended in cases of:

• Andropause, which is the natural decrease in testosterone levels in men

• Hypoactive sexual desire disorder, which is a persistent loss of sexual desire that causes personal distress, especially in postmenopausal women

• Hypogonadism, which is low hormone production by the sex glands and can occur in both men and women

• Loss of hormone function after chemotherapy, radiation therapy, or surgery that directly affects the testicles or ovaries, resulting in lower testosterone levels

These conditions can cause symptoms such as low libido, erectile dysfunction, constant fatigue, loss of muscle mass, fat accumulation, mood changes, irritability, insomnia, and difficulty concentrating.

Testosterone replacement therapy may be recommended to help relieve these symptoms and restore hormonal balance, improving quality of life and overall well-being.

Confirming a diagnosis

Based on the symptoms reported, a healthcare provider may order testosterone tests to measure total and, when appropriate, free testosterone levels.

Free testosterone is the fraction of testosterone that is not bound to proteins in the blood and is available for the body's tissues to use. It accounts for about 2% to 3% of total testosterone.

Testosterone levels vary by age and sex. According to the Endocrine Society, testosterone deficiency should only be diagnosed when symptoms are present and testosterone levels are consistently below the reference range. If these criteria are met, a healthcare provider may recommend testosterone replacement therapy.

TRT for men

Testosterone replacement therapy for men may include medications such as:

• Testosterone cypionate, testosterone enanthate, or testosterone undecanoate injections, given according to the schedule recommended by the doctor

• Testosterone gel, applied to the skin daily

• Testosterone pellets, implanted under the skin

Although testosterone levels in men naturally begin to decline with age, not every man with lower testosterone levels needs replacement therapy. It is important to see a healthcare provider so symptoms and blood test results can be evaluated before treatment is recommended.

TRT for women

Testosterone replacement therapy for women may include transdermal gels or creams applied to the skin in adjusted doses. It may also include subcutaneous pellets, which are implants that slowly release testosterone.

There are currently no FDA-approved testosterone products specifically indicated for women. According to the FDA, testosterone products approved in the US are indicated for males with testosterone deficiency, so use in women is considered off-label. Doctors may prescribe these products at adjusted doses when clinically appropriate.

Studies show that testosterone replacement therapy may improve some aspects of sexual function in women. However, data on long-term safety and effectiveness are limited, and results may vary from person to person.

A natural way to support healthy testosterone levels is to adopt healthy lifestyle habits, such as eating a balanced diet, exercising regularly, not smoking, avoiding alcohol, and reducing salt and fatty food intake.

TRT side effects

In some cases, testosterone replacement therapy may cause side effects, such as:

• Worsening of existing prostate cancer
• Changes in blood pressure or possible cardiovascular risks
• Increased red blood cell levels
• Development or worsening of sleep apnea
• Acne and oily skin
• Allergic skin reactions from topical products
• Breast enlargement

Testosterone replacement therapy should only be used under medical guidance and should not be used to gain muscle mass, as it can cause serious harm to health.

Can TRT cause cancer?

Testosterone replacement therapy does not appear to cause cancer. However, it may stimulate the growth of certain hormone-sensitive cancers that are already present, especially prostate cancer in men and breast cancer in women.

Using testosterone without a medical need, such as for cosmetic or performance-related purposes, can increase health risks because hormone levels may become uncontrolled.

Contraindications for use

In men, testosterone replacement therapy is not recommended for people with prostate cancer, as testosterone may stimulate tumor growth.

It should also be avoided in people with severe sleep apnea, serious liver or kidney disease, or a history of blood clots.

In women, testosterone therapy is usually contraindicated in cases of breast or uterine cancer, liver disease, severe unexplained hormonal changes, pregnancy, or breastfeeding.

People with normal testosterone levels should not use testosterone, as it may cause more harm than benefit.