Skip to content

Testosterone, Total (Serum or Plasma)

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

This test measures the amount of total testosterone, a key male sex hormone, in your blood. Testosterone helps regulate muscle mass, bone density, and sexual function.

Quick summary

["Your total testosterone level helps doctors assess hormone balance, especially in men with suspected low testosterone or related symptoms."]

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

Key facts at a glance

LOINC
59992-8
Short code
Testost sp4 p chal SerPl-mCnc
Synonyms
Testost sp4 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, or changes in mood and energy. It’s also used in evaluations for infertility, delayed puberty, or conditions like hypogonadism (low testosterone). Women may also get this test if they have unusual menstrual patterns or symptoms like acne or excessive hair growth.

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 lab uses a specific method. Avoid smoking or drinking alcohol for 24 hours before testing. If you’re on hormone therapy, let your provider know.

What the Results Mean

Results are compared to general reference ranges for your age and sex. Low levels may indicate hormonal imbalances, while very high levels could signal conditions like tumors or Cushing’s syndrome. Your provider will interpret results in the context of your symptoms and medical history.

Common Conditions Affecting Results

Factors like stress, illness, or certain medications (e.g., steroids) can temporarily alter testosterone levels. Obesity, aging, or chronic health conditions (like diabetes) may also influence results.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Total Testosterone

Frequently asked questions

What does a low total testosterone level mean?
A low total testosterone level may suggest conditions like hypogonadism (low testosterone production), pituitary disorders, or chronic illnesses. It can cause symptoms like fatigue, reduced sex drive, or muscle weakness. Your provider will discuss further testing or treatment options based on your symptoms and medical history.
What causes fluctuations in testosterone levels?
Testosterone levels can vary due to stress, sleep quality, exercise, medications (e.g., steroids), or underlying health conditions. Age, weight, and hormonal imbalances (like thyroid issues) can also play a role. If your levels seem inconsistent, talk to your provider about lifestyle changes or additional testing.
Can diet or supplements affect testosterone levels?
Certain foods, like zinc-rich foods or healthy fats, may support hormone balance, but diet alone won’t drastically change testosterone levels. Supplements like vitamin D or DHEA can sometimes help, but they’re not a substitute for medical evaluation. Always check with your provider before starting new supplements.
  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