What is testosterone?

Testosterone is an important sex hormone in males, and it is needed for a number of different things in the body, like:

• Development of the penis and testes
• Deepening of the voice during puberty
• Bone growth and strength
• Facial and pubic hair during and after puberty
• Muscle growth
• Sex drive 
• Sperm production

Both men and women have testosterone in their body, but women, whose testosterone is made in their ovaries, usually have a lot less compared with men. This page focuses on testosterone levels in men.

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What is a good testosterone level?

Generally, the normal total testosterone level in men is above 12 nmol/L, a borderline level is 8-12 nmol/L, and a low level is <8 nmol/L. These ranges may vary slightly depending on the laboratory which performs your test. 

As men get older, their testosterone levels steadily, but slowly decrease at a rate of about 1–2% each year. On top of this, testosterone levels in men naturally vary throughout the day – they’re usually at their highest in the morning and lowest in the late afternoon/evening. 

These changes in testosterone levels usually don’t cause any problems, but you might start to feel symptoms if your levels vary too much.

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What causes low testosterone?

Low testosterone levels or ‘hypogonadism’ can be caused by various factors, which are often grouped into ‘primary’ and ‘secondary’ depending on where the problem originates from. 

Primary causes of low testosterone

These suggest that there is a problem with the testicles themselves, which can be a result of:

• Damage or injury to the testicles
• Mumps
• Cancer treatment
• Having too much iron in your blood from conditions such as haemochromatosis
• ‘Klinefelter syndrome’ - this is a condition that can be present from birth, whereby men have additional ‘X’ chromosomes (as opposed to just having ‘X’ and ‘Y’). These extra chromosomes can affect the way the testicles develop.
• Undescended testicles - before birth, the testicles develop higher up in the body and move down or ‘descend’ to a permanent position towards the scrotum. Occasionally, one or more testicles might not descend properly, and if left uncorrected, can lead to problems with the testicles, and a subsequent lower testosterone.  

Secondary causes of low testosterone

In this case, there may be problems higher up in some parts of the brain which prevent the testicles from functioning as normal. This can be a result of:

• Medications, including opioid painkillers
• Obesity - being significantly overweight at any age can increase the risk of low testosterone levels
• Pituitary dysfunction - the pituitary gland, a part of the brain responsible for releasing hormones into your blood, may not be functioning normally
• HIV/AIDS - HIV/AIDS can reduce the amount of testosterone in your body through their effect on various parts of the brain.
• Aging - as men age, there is a progressive reduction in the amount of testosterone in their body. This rate varies from person to person.

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What happens when a man’s testosterone is low?

When levels of testosterone fall too much, it can affect men both physically and psychologically. A total testosterone level considered low enough to need treatment is below 12 nmol/L. Whether you’re having symptoms and whether you wish to have children in the future are other factors in deciding if treatment is right for you or not. Treatment should only be started following a face to face review with a doctor.

Some of the most common symptoms of low testosterone are:

• Reduced muscle growth
• Mood swings and irritability
• Increased body fat
• Body hair loss
• Wrinkled skin
• Decreased muscle tone
• Lack of enthusiasm and energy
• Erectile dysfunction 
• Osteoporosis
• Poor concentration and short-term memory
• Sleep difficulties

Some of the symptoms above could interfere with your daily life, so it's important to find the underlying cause and work out what can be done to resolve it.

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What happens if a man’s testosterone is too high?

When levels of testosterone become too high, some of the symptoms include: 

• Acne (common on the back and shoulders)

• Hair loss 

• Enlarged prostate 

• Minor testicle shrinkage

• Reduced fertility  

• Other risks associated with high testosterone levels even without symptoms are:

• Testicular tumours

• Increased risk of blood clots

• High red blood cell count

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How can I get tested for my testosterone level?

At Superdrug Online Doctor, we offer a home testosterone blood test kit, which you can use to check your total testosterone levels. Buying and using this test is a simple, convenient process:

• Place an order with us and your kit can be sent to your door or sent for in-store collection.
• This test will include a blood collection kit and pre-paid envelope. Your test should arrive at your address within 2 days of your order being placed.
• You’ll need to collect a small sample of blood (using the pin-prick lancet device included) with the kit and post it off to the lab for testing. Your results will be ready within 2 – 3 days of your sample reaching the lab, and we’ll let you know when you can see them in your account with advice about the results from one of our doctors.
• Take your test in the morning between 7am and 11am, before you’ve had anything to eat or drink (except water), otherwise your test results might not be accurate. Chat to your doctor first if you have been told you should not fast or are diabetic. Do not take the test if you’re feeling unwell.

If you’re not comfortable doing a test at home, then you can schedule an appointment with your doctor. Your doctor will know the best time to do your test and will be able to check more than just your testosterone level, which could give a bigger picture of your general health. 

If your test shows that you have low testosterone, it’s recommended that you repeat the test after at least 4 weeks for confirmation before making any decisions about further treatment. If a low total testosterone level is confirmed, you will need to have a complete check-up with your doctor to assess the cause and request a referral to a specialist before starting treatment.

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How can I get treatment for low testosterone?

If you have low testosterone levels, it’s likely that your doctor will recommend some changes in lifestyle first. These might include:

• Regular exercise
• Stress training
• Drinking less alcohol and not using illicit drugs
• Having a balanced diet 

After making these changes, if they’re not effective, or your levels are very low, your doctor might refer you to a specialist called an endocrinologist, who might recommend testosterone replacement therapy (TRT). There are different forms of this kind of therapy:

• Tablets
• Gels
• Patches
• Implants
• Injections

Remember, if you’re receiving treatment with testosterone, then you need to have follow-up blood tests to make sure you’re responding well to treatment (which can include home testing). If you and your doctor are happy, and you’re currently receiving testosterone replacement therapy, you could reorder one of the following treatments with us: 

• Tostran gel 2%
• Testogel sachets

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What are the side effects of testosterone treatment?

Even though testosterone replacement therapy is generally considered safe, it can be associated with some side effects. It’s a good idea to be aware of these, since it helps you look out for them while you receive treatment. Some of the side effects include:

• Mild fluid retention
• Increased risk of prostate issues
• Breast enlargement
• Acne or oily skin
• Decreased testicle size
• Increased mood swings

Not all side effects can be seen, and you might be recommended to get some tests done to check for changes while you’re receiving testosterone treatment. Some of the side effects you can test for include:

• Changes in cholesterol levels
• Increased red blood cell count
• Decreased sperm count (this can cause infertility)

Remember that if you’re receiving testosterone replacement therapy, regular follow-up appointments with your doctor is always important. You should let them know if you’re experiencing any side effects, even if you don’t think they’re serious. Your doctor might be able to make some suggestions that can help. 

If you experience any of these rare, serious side effects, then you should contact emergency services immediately:

• Signs of an allergic reaction – hives, difficulty breathing, swelling of parts of the face or tongue
• Nausea/vomiting 
• Changes in skin colour
• Difficulty breathing
• Swelling of the ankles/feet
• Sexual performance issues: erectile dysfunction, or difficulty with ejaculation and semen production
• Painful/difficult urination 
• Signs of blood clots in the legs (swelling/pain), or lungs (chest pain, shortness of breath, dizziness)
• Signs of liver problems such as dark urine, appetite loss, jaundice (yellowing of the eyes and skin), upper stomach pain

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Sources

Medical News Today (2019). Why do we need testosterone? [online] Available at: https://www.medicalnewstoday.com/articles/276013 [accessed 6 February 2019].

Medicine Net (2019). High and low testosterone levels in men. [online] Available at: https://www.medicinenet.com/high_and_low_testosterone_levels_in_men/views.htm [accessed 6 February 2019].

Medline Plus (2017). Could you have low testosterone? [online] Available at: https://medlineplus.gov/ency/patientinstructions/000722.htm [accessed 6 February 2019].

NCBI (2018). Physiology, testosterone. [online] Available at: https://www.ncbi.nlm.nih.gov/books/NBK526128/ [accessed 6 February 2019].

NCBI (2014). Adverse effects of testosterone replacement therapy: an update on the evidence and controversy. [online] Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4212439/ [accessed 6 February 2019].

NHS (2019). Male menopause. [online] Available at: https://www.nhs.uk/conditions/male-menopause/ [accessed 6 February 2019].

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