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Low testosterone (androgen deficiency)

Androgen deficiencyTestosterone is a hormone that teenage boys and men make in their testicles. They need it to develop during puberty, make sperm, and develop and maintain a sex drive. It also helps them to build and maintain strong muscles and bones.

If you have low testosterone (androgen deficiency), it means your testicles don't make enough testosterone. This can happen for several reasons.

Sometimes it happens because there is a problem with your testicles – either something you were born with, or a later injury or infection.

Sometimes another medical problem – like diabetes, heart disease, or obstructive sleep apnoea – reduces the amount of testosterone your body makes.

Other times a problem in part of a man's brain (their pituitary gland or hypothalamus) means their testicles don't produce as much testosterone as they should.

How do I know if I have low testosterone?

If you have low testosterone you will notice some of the following symptoms:

When you go to see your doctor, they will ask what symptoms you have. They will also check the amount of body hair you have, as well as the size of your penis and testicles.

You will need to have a blood test, to check the amount of testosterone in your blood. This test needs to be done early in the morning, and if it shows a low level you will need a second test on another day to confirm it.

How is low testosterone treated?

If your blood tests show you have low testosterone, you may need to see a specialist hormone doctor, called an endocrinologist (en-do-crin-ol-o-gist). They may suggest you are treated with testosterone, either in tablets, patches, or injections.

The aim of treatment is to get your testosterone levels normal. Other than that, you may have specific personal goals, like getting or keeping a deep voice, growing a beard and pubic hair, improving your sex drive and erections, or strengthening your muscles and bones.

Before having testosterone treatment, you will need to have another test, checking your red blood cell count. You will need to have this test once a year, as testosterone treatment can increase your red blood cell level.

Testosterone treatment could be dangerous if you have, or have had, prostate cancer. Your doctor will talk to you about whether you need to be checked for this, or whether you need any regular monitoring.

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Written by HealthInfo clinical advisers. Last reviewed August 2016.


Page reference: 70631

Review key: HIAND-70631