Testosterone (Serum or Plasma, Mass Concentration)
This test measures the amount of testosterone, a key male sex hormone, in your blood. Testosterone plays a role in muscle and bone development, as well as sexual function and mood.
["Testosterone helps with energy, muscle strength, and reproductive health."]
Key facts at a glance
- LOINC
- 47945-1
- Short code
- Testost 3D p 5000 U HCG IM SerPl-mCnc
- Synonyms
- Testost 3D p 5000 U HCG IM SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 80
- Ref high
- 200
- Critical range
- 20 N/A – 400 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84436
- SNOMED
- 302346007
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Might You Need This Test?
Your doctor may order a testosterone test to check for low or high levels, which can affect fertility, energy, or symptoms like fatigue, low libido, or changes in body hair. It’s often done if you have symptoms of hormone imbalance, such as unexplained weight changes or mood swings.
Common Reasons for Testing
Common reasons include evaluating male infertility, diagnosing conditions like hypogonadism (low testosterone), or monitoring hormone-related treatments. Women may also get this test if they have symptoms linked to hormonal imbalances, though testosterone levels are generally lower in females.
Sample Collection and Preparation
A blood sample is taken from a vein, usually in your arm. You may need to fast for 8–12 hours before the test, depending on your doctor’s instructions. Avoid smoking or consuming alcohol before the draw.
What to Expect During the Test
The process is quick and usually painless. You’ll lie down or sit comfortably while the nurse inserts a small needle into your arm. After drawing blood, the site is cleaned and bandaged. Results are typically ready within a few days.
Reference range
Adult: 80-200 ng/dLN/A
Take your thyroid medication after the blood draw if applicable. No fasting required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Testosterone Level
Frequently asked questions
Low testosterone can cause fatigue, reduced muscle mass, mood changes, or difficulty concentrating. High levels may lead to acne, excessive body hair, or menstrual irregularities in women. Testosterone levels can also be influenced by age, medications, or chronic health conditions like obesity or diabetes.
Talk to your doctor if you experience persistent symptoms like fatigue, low libido, or changes in body hair or mood. They may recommend a testosterone test or other hormone evaluations to determine the best course of action.
Your doctor will discuss the results with you and explain what they mean in the context of your health. They may recommend further testing, treatments, or lifestyle changes to help manage any imbalances.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy