HomeLab TestsTestosterone Levels Test
Back to Lab Tests
Testosterone Levels Test
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Lab Tests

Testosterone Levels Test

A testosterone levels test measures the amount of the hormone testosterone in your blood to help diagnose conditions related to abnormal hormone levels, such as puberty issues or reproductive health concerns.

What is a testosterone levels test?

This test measures the amount of testosterone in your blood. Testosterone is a hormone that controls the actions of certain cells or organs. While often considered a male sex hormone, it is present in females in smaller amounts. In both sexes, it helps control sex drive and supports muscle and bone growth. In males, it is also involved in body hair growth, voice deepening, sperm production, red blood cell production, and height increases.

Testosterone in the blood is either bound to proteins (like sex-hormone-binding globulin or albumin) or unbound (free). Free testosterone is more available for the body to use. Providers may order one of three tests:

  • Total testosterone test: Measures both bound and free testosterone (the most common test).
  • Free testosterone test: Measures only the unattached form.
  • Bioavailable testosterone test: Measures free testosterone and testosterone attached to proteins other than SHBG.

Why do I need a testosterone levels test?

You may need this test if you have symptoms of abnormal testosterone levels. In children and teens, it is used to investigate early or delayed puberty.

Symptoms of low testosterone (males)

  • Low sex drive.
  • Erectile dysfunction (ED).
  • Infertility.
  • Enlarged breasts.
  • Lack of face or body hair.
  • Thinning bones or anemia without a known cause.
  • Loss of muscle mass.

Symptoms of high testosterone (females)

  • Abnormal hair growth on the face or body.
  • Hair loss on the head (male-pattern baldness).
  • Voice changes.
  • Irregular or absent menstrual periods.
  • Infertility.
  • Acne.

What happens during a testosterone levels test?

The test involves a blood draw, typically performed in the morning between 7 and 10 a.m., when levels are highest. A health care professional collects a blood sample from a vein in your arm using a small needle. At-home kits for blood or saliva collection are also available; consult your provider to see if this is appropriate for you.

Will I need to do anything to prepare for the test?

You may be required to fast for several hours before the test. You should also inform your provider of all medications you are taking, as some may need to be stopped temporarily. Do not stop taking any medication unless instructed by your provider.

Are there any risks to the test?

There is very little risk. You may experience slight pain or bruising at the needle site, but symptoms typically resolve quickly.

What do the results mean?

Abnormal results, when paired with symptoms, may indicate a health problem. It is important to note that testosterone levels naturally decrease with age.

  • In males, low levels may be caused by: Testicular problems, chronic diseases (liver or kidney), pituitary gland disorders, benign tumors, injury, alcohol use disorder, or genetic diseases like Klinefelter syndrome.
  • In females, low levels may be caused by: Adrenal, pituitary, or ovarian disorders.
  • In males, high levels may be caused by: Testicular tumors, steroid use, or adrenal gland disorders (e.g., congenital adrenal hyperplasia).
  • In females, high levels may be caused by: Polycystic ovary syndrome (PCOS), ovarian cancer, adrenal gland disorders, or pituitary gland disorders.

Frequently Asked Questions

Total testosterone measures both bound and unbound hormone and is the standard initial screen. Free testosterone reflects the biologically active fraction and is more informative when binding protein levels are abnormal (e.g., obesity, aging, estrogen therapy). If you have conditions that alter SHBG or albumin, request a free or bioavailable testosterone test for a clearer picture.
fter initiating therapy, testosterone levels typically plateau within 2‑4 weeks for injections, 4‑6 weeks for gels or patches, and up to 8‑12 weeks for oral formulations. Your provider will usually re‑check levels after the first month and then periodically to fine‑tune the dose.
Women can have testosterone measured when they present with hirsutism, acne, menstrual irregularities, or unexplained infertility. Normal adult female total testosterone ranges are roughly 15‑70 ng/dL (0.5‑2.4 nmol/L), but labs vary. Interpretation should always consider clinical context and other androgen levels.
Yes. Drugs such as glucocorticoids, opioids, certain antidepressants (e.g., SSRIs), and anabolic steroids can suppress or artificially elevate testosterone levels. Inform your clinician about all medications and supplements (including herbal products) before testing so they can interpret the results accurately.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

kontakt@hittavard.se

Ⓒ 2024. Alla rättigheter förbehålls av juxt ab

Sök
Om ossVillkor och policyVanliga frågorKontakta oss