Serum or plasma concentration of free testosterone (qualitative screening)
This test measures the amount of free (unbound) testosterone in your blood, which is an important form of the hormone that helps regulate male and female sex characteristics.
["Free testosterone screening helps assess hormone balance and potential hormone-related conditions."]
Key facts at a glance
- LOINC
- 28161-8
- Short code
- NEEDHELPLETTINGGO
- Synonyms
- —
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- reported-living-hiv
- 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 This Test Is Done
Your healthcare provider may order this test to evaluate hormone levels, especially if you have symptoms like low libido, irregular menstrual cycles, or signs of hormonal imbalances. It can also be part of a broader evaluation for conditions like hypogonadism (low testosterone) or polycystic ovary syndrome (PCOS).
What to Expect Before the Test
No special preparation is needed, but you may be asked to fast for 8–12 hours before the test if it involves drawing blood from a vein. Avoid alcohol or strenuous activity for 24 hours beforehand. If you’re taking medications that affect hormones, let your provider know.
During the Test
A healthcare professional will draw blood from a vein in your arm. The process is quick and usually causes only mild discomfort. The blood sample is then sent to a lab for analysis to measure free testosterone levels.
What the Results Mean
Results are qualitative (yes/no) rather than quantitative, meaning they indicate whether free testosterone levels are within expected ranges or outside them. Your provider will interpret the results in the context of your symptoms and medical history.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Free testosterone screening
Frequently asked questions
Free testosterone screening helps identify hormonal imbalances that may require treatment. Low levels could suggest conditions like hypogonadism, while abnormal results may prompt further testing for conditions like Cushing’s syndrome or androgen insensitivity.
How long will I need to wait for my results?
Can I eat or drink before this test?
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 16, 2026. · Read our editorial policy