Skip to content

Testosterone, Total (Serum or Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the total amount of testosterone, a key male sex hormone, in your blood. It can help diagnose hormonal imbalances, fertility issues, or conditions affecting hormone production.

Quick summary

["Total testosterone levels help assess hormone health and potential hormone-related concerns."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
59989-4
Short code
Testost sp7 p chal SerPl-mCnc
Synonyms
Testost sp7 p chal SerPl-mCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
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 Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms like low libido, fatigue, irregular menstrual cycles (in women), or unexplained infertility. It could also be part of routine screening for hormonal disorders or before certain treatments.

What to Expect Before the Test

No special preparation is needed, but you may be asked to fast for 8–12 hours before the draw if your test involves a fasting sample. Wear a loose shirt for easy access to your arm. Avoid smoking or caffeine for 30 minutes before the blood draw.

How the Test Works

A small amount of blood is drawn from a vein in your arm. The sample is then sent to a lab where it is analyzed using an immunoassay method to measure testosterone levels accurately.

What the Results Mean

Results are compared to general reference ranges, but individual needs may vary. Low or high levels can signal underlying health concerns that require further evaluation by your provider.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Total Testosterone

Frequently asked questions

What causes abnormal testosterone levels?
Abnormal testosterone levels can result from conditions like pituitary disorders, kidney or liver disease, tumors (benign or malignant), or certain medications. Lifestyle factors, such as obesity, smoking, or chronic stress, may also influence hormone balance.
How long does it take to get results?
Results are typically available within 1–3 business days, depending on your lab’s processing time. Your healthcare provider will discuss the findings with you during your follow-up visit.
Can I adjust my diet or activity before the test?
While fasting may be required for some tests, avoid extreme dietary changes or supplements (like herbal products) that could affect hormone levels. Always follow your provider’s specific instructions.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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