Health Encyclopedia

 

Health Encyclopedia Home



Total TestosteroneTestosterona total

Total Testosterone

Does this test have other names?

Testosterone (total)

What is this test?

This test measures the level of the hormone testosterone in your blood. Testosterone is a male sex hormone that helps masculine features develop. Testosterone is made in the testes and the adrenal glands, and causes the changes that occur in boys during puberty. Testosterone encourages the growth of hair and muscles, as well as the penis and testes. Testosterone also causes a boy's voice to deepen. Grown men continue to make testosterone, which promotes sex drive and encourages the production of sperm.

Women's ovaries also produce small amounts of testosterone.

Normally, the hypothalamus area of the brain controls the pituitary gland, which regulates the amount of testosterone your body makes. If testosterone levels are too low or too high, you can have problems with sex drive and fertility. Low testosterone, called hypogonadism, is a common problem. 

This test is usually done in the morning, because testosterone levels tend to be highest at that time. But you may need to have this test more than once, and at different times of the day, to confirm low testosterone levels.  This is necessary because your testosterone level can change from morning to evening and from day to day. 

Why do I need this test?

You may need this test if you have symptoms of low testosterone.

Symptoms of low testosterone in men include:

  • Large breasts

  • Low sex drive or lack of interest in sex

  • Difficulty getting an erection

  • Low sperm count and other fertility problems

  • Changes in the testicles

  • Weak bones

  • Irritability

  • Difficulty concentrating

  • Loss of muscle mass

  • Hair loss

  • Depression

  • Fatigue

  • Anemia

Symptoms of low testosterone in women include:

  • Fertility problems

  • Missed or irregular menstrual periods

  • Osteoporosis

  • Low sex drive

  • Changes in breast tissue

  • Vaginal dryness 

What other tests might I have along with this test?

Your doctor may order other blood tests to check hormone levels, including:

  • Follicle-stimulating hormone, or FSH, test

  • Luteinizing hormone, or LH, test

You may also need to have:

  • Biopsy of the testicles

  • Imaging test, such as an MRI

  • Semen analysis

  • Tests of the pituitary gland 

What do my test results mean?

Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.

The results of this test are given in nanograms per deciliter (ng/dL). Normal test results show total testosterone levels of:

  • 280 to 1,100 ng/dL for men

  • 15 to 70 ng/dL for women

If your testosterone levels are lower than normal, you may have a condition that affects your testosterone production. If your testosterone levels are higher than normal, you may have a tumor on the testes or ovaries that affects your testosterone production. 

How is this test done?

The test requires a blood sample, which is drawn through a needle from a vein in your arm. For the most accurate results, the sample is usually taken early in the morning, preferably around 8 o'clock.

Does this test pose any risks?

Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore. 

What might affect my test results?

Some medications may affect your test results. These include antifungal medications, such as ketoconazole, and hormone medications. Having the test performed late in the day may show that your testosterone level is lower than it really is.

How do I get ready for this test?

You don't need to prepare for this test. But be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use. 

 
Related Items
Wellness Library
  Why the Doctor Takes a Blood Sample
Content Type 167
  Acetylcholine Receptor Antibody (Blood)
  Albumin (Blood)
  Alpha-Fetoprotein (Blood)
  Alpha-Fetoprotein Tumor Marker (Blood)
  Ammonia
  Amphetamine Screen (Blood)
  Amylase (Blood)
  Angiotensin Converting Enzyme (Blood)
  Antidiuretic Hormone
  Antimitochondrial Antibody and Antimitochondrial M2 Antibody
  Apolipoprotein A
  Apolipoprotein B100
  Benzodiazepines (Blood)
  Bicarbonate
  Direct Bilirubin
  BNP (Blood)
  C-Peptide (Blood)
  CA 125
  CA 19-9
  CA 27-29
  Calcium (Blood)
  Carcinoembryonic Antigen
  Cardiac Biomarkers (Blood)
  Total and Free Carnitine
  Catecholamines (Blood)
  Ceruloplasmin (Blood)
  Chloride
  Cholesterol
  Cholinesterase (Blood)
  Clonazepam Drug Level (Blood)
  Creatine Kinase (Blood)
  Creatinine Clearance
  Creatinine (Blood)
  Cystatin C
  D-Dimer
  Dehydroepiandrosterone and Dehydroepiandrosterone Sulfate
  Digoxin Drug Level
  Erythropoietin (Blood)
  Estradiol (Blood)
  Ethanol (Blood)
  Ferritin (Blood)
  Fluphenazine Drug Level (Blood)
  Folate
  Follicle-Stimulating Hormone
  Free Androgen Index
  Gastrin
  Growth Hormone with Stimulation (Blood)
  Growth Hormone with Suppression (Blood)
  Growth Hormone (Blood)
  HCG (Blood)
  HDL Cholesterol
  Insulin-Like Growth Factor
  Total and Free Insulin (Blood)
  Iron (Blood)
  Iron and Total Iron-Binding Capacity
  Ketone Bodies (Blood)
  Lactose Tolerance (Blood)
  LDL Cholesterol
  Adult Lead (Blood)
  Lead (Blood)
  Leptin (Blood)
  Lipase
  Lipid Panel with Non-HDL Cholesterol
  Lipoprotein-Associated Phospholipase A2
  Lithium
  Lipoprotein(a) Cholesterol
  Luteinizing Hormone (Blood)
  Magnesium (Blood)
  Mercury (Blood)
  Metanephrines (Blood)
  Methylmalonic Acid (Blood)
  Myoglobin (Blood)
  Pancreatic Polypeptide
  Parathyroid Hormone
  Progesterone
  Proinsulin (Blood)
  Prolactin (Blood)
  Salicylate (Blood)
  Free Light Chains (Blood)
  Sodium (Blood)
  Free and Bound Triiodothyronine (Blood)
  Free and Bound T4
  Tartrate-Resistant Acid Phosphatase
  Tegretol (Blood)
  Free Testosterone
  Theophylline
  Thyroid Antibody
  Thyroid Antithyroglobulin Antibody
  Thyroid Stimulating Hormone
  Total Copper (Blood)
  Transferrin
  Tricyclic Antidepressant Screen
  Triglycerides
  Troponin
  Trypsin (Blood)
  Blood Urea Nitrogen
  Uric Acid (Blood)
  VLDL Cholesterol