Total Testosterone Test

What is Testosterone?

Testosterone is a sex hormone produced by both men and women. Testosterone is made in large amounts by the testes (or testicles) in men, and in smaller amounts in the ovaries in women and in the adrenal glands in both men and women.

In men, its roles include the development of sex organs, deepening voice, facial/body hair growth (and balding), sex drive (libido), mood, bone and muscle mass and strength, body fat distribution, and sperm and red blood cell production. The roles of testosterone in women include fertility, ovarian function, libido, and bone mass and strength.

Testosterone levels in the body are controlled by the pituitary gland, which receives signals from the hypothalamus in the brain. The pituitary releases hormones that travel in the blood to the testes, ovaries, and adrenal glands, where they stimulate the production of testosterone. Control of the testosterone level in the blood is managed by the pituitary, which sends fewer hormones to the testes/ovaries/adrenals when testosterone levels rise above normal and more hormones when testosterone levels fall below normal.

Testosterone levels decline with age. In men, starting from about 40 years of age, the level decreases about 1-2% per year. Over one-third of men over 45 years of age may have testosterone levels lower than those considered 'normal' (hypogonadism).

What is a Total Testosterone test?

A testosterone test measures the level of testosterone in the blood. In the blood, testosterone is either bound to proteins or unbound free testosterone. Most testosterone is bound to the proteins, albumin and sex hormone binding globulin, while only 2-4% of the total testosterone is unbound (free) testosterone and able to enter cells. Albumin is not bound securely to testosterone and can become unbound. Together, albumin-bound and free testosterone are called bioavailable testosterone. A total testosterone test measures the blood levels of the three testosterone types, protein-bound, bioavailable, and free testosterone. Click here to read about the free testosterone test.

Why is a Total Testosterone test important?

In men, when testosterone levels are lower or higher than normal then it may be due to a disorder that affects testosterone production. Low testosterone levels in men may suggest a genetic disorder such as Klinefelter syndrome or abnormal development of the sex organs, or accidental testicular injury. In men and women, low testosterone levels may suggest a disorder of the hypothalamus in the brain (controls the pituitary) or the pituitary gland such as a tumour or Addison's disease, or because of removal of the testes or ovaries.

Causes of low testosterone levels in men also include infection (e.g., mumps virus, COVID-19), autoimmune diseases, metabolic syndrome (high blood pressure, high cholesterol levels, abdominal fat, and high blood sugar level), kidney and liver disease, and AIDS/HIV. Therapies such as chemotherapy or radiation that damage the testes, and medicines such as opioid pain medications, the anti-fungal ketoconazole, cimetidine (treats heartburn and stomach ulcers), and some antidepressants may also lower this hormone. However, low testosterone levels are beneficial to men with prostate cancer, as this hormone may stimulate prostate cancer growth. In women, oestrogen therapy can result in low testosterone levels.

In men, high testosterone levels may suggest a testicular or adrenal gland cancer, and in women, polycystic ovary syndrome, or ovarian or adrenal gland cancer.

Please note that high or low testosterone levels do not necessarily indicate any of the conditions listed above. A medical interpretation of your test result with The Online Clinic is provided as a standard element of our service, along with any follow-up recommendations.

Who should monitor their Total Testosterone?

A total testosterone test is recommended for all men as part of their Well Man health check, which assesses your current health and identifies early signs of disorders potentially adversely affecting their health. Men are also advised to get themselves tested if there is a family history of fertility issues, testicular cancer or prostate cancer.

This test is particularly important if a man or woman has or develops symptoms associated with low or high testosterone. When testosterone levels are lower than normal, men and women can experience loss of libido, loss of bone mass, fertility problems, a low mood, poor concentration, and bone and muscle weakening. Men can also have erectile problems, low sperm count, impotence, loss of body/head/facial hair, loss of muscle mass, irritability, and increased breast size, while women may have an irregular menstrual cycle, breast tissue changes and vaginal dryness.

However, when levels of this hormone are higher than normal, symptoms in men can include low sperm counts, testicle shrinkage, impotence, prostate enlargement, mood swings, weight gain, increased muscle mass, and increases in signs associated with cardiovascular disease (such as high blood pressure, blood cholesterol level, and blood clotting risk). Women with high testosterone levels can have reduced fertility, irregular menstrual cycle, reduction in breast size, deep voice, excess facial/body hair, male-pattern baldness, thickened skin, and depression.

How to test for Total Testosterone?

The testosterone level in the blood is lower at later times of the day. Guidelines therefore recommend measuring levels between 7 am and 11 am. Although there is a lack of evidence supporting testing in the fasting state, this is the recommendation of the European Association of Urology for male patients.

Total blood testosterone level is one of the most important measures of testosterone deficiency. Total testosterone tests can easily be done using a blood sample taken by yourself using a simple self-collection test kit. The test kit contains full instructions how to collect the blood sample. To get the best sample for testing, read and follow the instructions given, collect the full 600 mcl blood sample from your little finger (which is up to the top line on the side of the collection tube), and mix the sample by gently inverting the tube 5-6 times after collection. Your healthcare professional will receive the test results, interpret what they mean, and inform you of their findings.

If you are using a topical testosterone preparation, you must not extract the blood from any finger that may have come into contact with the testosterone cream or gel in the previous 4 weeks, as this can lead to distorted test results. Our recommendation is for patients to wear disposable gloves when applying the testosterone product to the skin. This should eliminate the risk of contamination of your blood sample with residue if you are careful not to touch the area of skin where you have applied the topical preparation.

What are normal Total Testosterone test results?

Testosterone test results vary with age, sex, medical history, medicines, and the test method. Reference ranges also vary between laboratories. Your doctor will therefore explain what your test results mean.

How to maintain or achieve good Total Testosterone levels

While testosterone levels will gradually decline with age, eating a balanced diet, maintaining the ideal body weight for your height, and exercise as well as plenty of rest and avoiding stress may help to achieve/maintain appropriate testosterone levels.

If you do have symptoms of low or high testosterone, please see your doctor. Testosterone therapy is available for those who need it, and your total testosterone level should be tested before treatment begins. However, you should be aware that although testosterone therapy may help some symptoms, such as erectile function, low libido, reduced bone and muscle mass, and low mood, it may not be effective at improving your energy levels and quality of life, or addressing issues requiring lifestyle changes (e.g., blood sugar and cholesterol levels).

The Online Clinic is able to prescribe a testosterone replacement therapy (TRT) called Androfeme for some female patients. We do not prescribe TRT for male patients, as a face to face assessment is required.

Reviewed by: Dr Loraine Haslam MBBS, DRCOG, DFSRH, LoC SDI, LoC IUT, MRCGP
GMC registration number: 4524038
Date: 24 November 2022
Next review: 23 November 2024
All UK registered doctors can have their registration checked on
The Medical Register at the GMC website.

Information Leaflet

Source and further information

Download Testosterone Information Leaflet