Is Testosterone Replacement Therapy Safe?

elderly man smiling whilst being outside

Low testosterone levels or low T can cause various problems and the benefits of testosterone replacement therapy (TRT) can be significant. If you are considering testosterone replacement, it is important to consider if it is right for you and understand the risks to make an informed decision.

At Harley Street MD in London, we always want our clients to know as much as possible about any treatment we can provide. This is why we offer a free consultation with a UK testosterone expert. We aim to answer your questions in this post so that you may better understand the benefits and risks of safe testosterone replacement therapy. 

Testosterone and Age: You can do many things to stay healthy as you age, including eating a high protein, low-fat diet, not smoking, and keeping active. But one consequence of ageing for some men is a decrease in testosterone levels

After the age of 30 to 40, testosterone typically starts to decline by around 1% a year. This means that depending on when your levels start to decline, men will often benefit from testosterone replacement around the age of 50 to 60.  

Symptoms of lower testosterone levels include:

Reduced sex drive 

Difficulty getting erections 

Increased body fat 

Reduced muscle bulk and strength

Decreased bone density 

Swollen or tender man boobs (gynecomastia) 

Hair loss 

Lower energy levels

Mood swings


Cognitive decline. 

Of course, it is unlikely that you will experience all of the above side effects as a result of low testosterone levels. There are also other reasons you could suffer from any of the above symptoms, including thyroid issues, side effects from medications, diabetes, and mental health conditions.

What Can Cause Low Testosterone?

Although testosterone will naturally decrease as you age, it is possible to experience low testosterone levels at any age. This may be a result of factors including: 


Being overweight

A sedentary lifestyle


Past use of Steroids

Hyperthyroidism (thyroid dysfunction).

What Is the Best Way to Diagnose Low Testosterone?

Before starting testosterone replacement therapy, you need to have an accurate diagnosis of low testosterone levels. There are testosterone testing kits that can be purchased to use at home. However, if the results are inaccurate or not correctly interpreted, you could be wasting your money. 

A full TRT screening at a clinic specialising in testosterone therapy, such as Harley Street MD in London, is the safest way to ensure an accurate diagnosis. During a full TRT screening, you will have additional tests, including anaemia, leukaemia, kidney and liver function, bone metabolism, diabetes, thyroid function, and prostate cancer. You can start testosterone replacement therapy on the same day you receive your diagnosis, following your screening. 

Benefits of Testosterone Replacement Therapy

The benefits of testosterone replacement are far-reaching and can drastically improve symptoms of low testosterone.

Additionally, there are other health benefits that can increase the overall quality of life.

The most common benefits include:

Increased sex drive

Higher energy levels

Improved mental clarity

Reduction of body fat and increase in muscle mass

Lower risk of osteoporosis.

Once you start to feel the benefits of testosterone therapy, other positive lifestyle changes are often much easier to implement. With increased energy, you might enjoy getting more active, and a good sex life can have a range of positive effects on your health. 

Although improved mental clarity isn’t going to protect from dementia. Research does indicate that a combination of regular exercise and keeping the brain active may lower the chance of cognitive decline.

Testosterone Replacement Therapy and Erectile Dysfunction (ED)

One of the reasons you may be interested in testosterone replacement is if you struggle with erectile dysfunction (ED). Getting an erection without the need for viagra can help to give you the confidence to start a new relationship or reconnect with your partner sexually. Low testosterone levels have been linked to difficulty getting or maintaining an erection. 

Our clinic in London has helped hundreds of men with erectile dysfunction. Many of our clients have told us that since starting testosterone therapy, they find it easier to get an erection and have noticed a boost in their sex drive. However, if low testosterone is not diagnosed at your TRT screening, we can provide you with alternative treatment options. 

Risks of Testosterone Replacement Therapy

Research supports the safety of testosterone replacement, but a small percentage of men do experience short-term and long-term side effects.

Short-term side effects of testosterone therapy include:

Acne or skin rash

Sleep apnea — breathing stops and starts when sleeping, 

Breast swelling or tenderness, 

Swelling in the ankles.

Long-term testosterone therapy may increase the risk of: 

High red blood cell counts could increase the risk of blood clots

Cardiovascular problems


Reduced sperm production and testicle shrinkage.

What Is the Best Way to Take Testosterone Replacement Therapy?

Testosterone therapy is available in skin and gum patches, gels, injections, and subcutaneous pellets. The best way to take testosterone replacement therapy will depend on your preference and how your body reacts. 

TRT Options



Patch (skin)

Simple to use

Skin rashes

Buccal patch (gum)

Simple to use

Irritation and gum disease


More control over dose

Must avoid clothing in contact with area applied for several hours

Nasal gel

More control over dose

May cause nasal problems


Inexpensive and convenient

Testosterone levels fluctuate between injections.

Subcutaneous pellets

Convenient and last for three to six months

Require minor surgery and can not be removed without surgery. 

Testosterone Replacement Therapy Monitoring

You will require blood tests at three and six months after starting testosterone replacement therapy. You will then need an annual test to check you’re on the correct dose of testosterone therapy. Red blood cell levels will also be checked when you have blood tests. 

Additional tests may include a bone density test if you have osteoporosis, and prostate cancer tests, if you had elevated PSA levels when you started your testosterone therapy. There is no limit on how long testosterone replacement therapy can be taken; typically, men remain on it long-term to prevent a recurrence of the symptoms of low testosterone. 

Don’t risk an incorrect diagnosis; come to our clinic in London for hormone level tests with our UK-qualified doctors are testosterone experts. Further to a full TRT screening and diagnosis, you will have immediate access to testosterone replacement therapy. Book a free consultation at our London clinic for confidential advice about TRT.

Founder at Harley St M.D.
Dr. Chia Tan is a UK trained medical doctor that specialises in cosmetic and aesthetic medicine and testosterone replacement therapy. He is qualified as a medical doctor since 2003 and has since trained extensively. He has been featured in several leading magazines as well as invited to appear on TV to discuss aesthetic medicine and the latest cosmetic procedures.
Dr. Chia Tan
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