Testosterone plays an important role in men’s sexual health, muscle mass, bone health, energy, and overall well-being. When testosterone levels are lower than expected, some men may experience symptoms such as reduced sex drive, erectile dysfunction, fatigue, or changes in muscle mass. However, these symptoms can have many possible causes, so they do not necessarily mean that testosterone is low.
A testosterone test is a blood test used to measure testosterone levels and help healthcare providers determine whether further evaluation is needed. Knowing when to test testosterone is important because testosterone levels naturally change throughout the day, and a single abnormal result does not always confirm a testosterone deficiency.
In this guide, we’ll explain what a testosterone levels test measures, when men may need testing, the best time of day to have a testosterone blood test, and what factors can affect the results.
What Is a Testosterone Test?
A testosterone test is a blood test that measures the amount of testosterone circulating in the bloodstream. It is commonly used when a healthcare provider suspects that a man may have testosterone deficiency based on his symptoms, medical history, or certain health conditions.
The test usually starts with measuring total testosterone. Depending on the clinical situation and the initial results, a provider may also consider free testosterone, which represents the portion of testosterone that is not tightly bound to blood proteins.
Importantly, a testosterone test is not interpreted in isolation. A diagnosis of testosterone deficiency generally requires both compatible symptoms or signs and consistently low testosterone measurements. Specialists recommend confirming low levels with a repeat morning fasting measurement rather than relying on a single result.
What Does a Testosterone Test Measure?
A testosterone blood test can measure different forms of testosterone depending on what your healthcare provider is evaluating.
For most men being evaluated for possible testosterone deficiency, total testosterone is the starting point. Free testosterone may be considered when clinically appropriate, using an accurate testing method and an appropriate reference range.
Because testosterone levels can vary across measurements, healthcare providers may repeat the test if the first result is low or does not align with the clinical picture. Some specialists recommend obtaining two early-morning total testosterone measurements on separate occasions before diagnosing testosterone deficiency.
Why Do Doctors Order Testosterone Tests?
Doctors may order a testosterone test when there is a clinical reason to suspect testosterone deficiency or another condition affecting testosterone production.
The purpose of testing is not simply to find out whether a testosterone number is "high" or "low." Instead, the result can help a healthcare provider determine whether the symptoms and medical history are consistent with testosterone deficiency and whether additional evaluation may be necessary.
A testosterone test may also be part of a broader assessment when a provider is investigating reproductive or hormonal concerns. If testosterone is repeatedly low, additional testing may be needed to help identify whether the problem is related to the testicles, pituitary gland, hypothalamus, medications, or another underlying condition.
This is why testosterone testing is best viewed as one part of a medical evaluation, rather than a standalone test that can diagnose a condition on its own.
When Should Men Get a Testosterone Test?
Men may need a testosterone test when they have symptoms or signs that could be related to testosterone deficiency, particularly when those symptoms are persistent or occur alongside relevant medical conditions.
However, symptoms alone cannot confirm low testosterone. Many of the symptoms associated with testosterone deficiency, such as tiredness, low mood, reduced concentration, or changes in sexual function, can also occur because of other health conditions or lifestyle factors.
Signs and Symptoms That May Prompt Testing
A healthcare provider may consider a low testosterone test when a man has symptoms that could indicate testosterone deficiency.
Some of the symptoms that may prompt evaluation include:
- Low sex drive: A noticeable or persistent decrease in sexual desire.
- Erectile dysfunction: Difficulty achieving or maintaining an erection can be associated with low testosterone, although ED has many other possible causes.
- Low energy or persistent fatigue: Reduced energy can occur with testosterone deficiency but is not specific to it.
- Reduced muscle mass or strength: Testosterone helps maintain muscle mass and physical function.
- Mood or concentration changes: Some men may experience changes in mood, motivation, or ability to concentrate.
- Infertility: Low testosterone can be associated with reproductive problems and may warrant hormonal evaluation.
It is important to remember that having one or more of these symptoms does not automatically mean that testosterone is low. For example, fatigue and mood changes can have numerous causes, while erectile dysfunction may be related to vascular, metabolic, psychological, medication-related, or other factors.
For this reason, a healthcare provider will generally consider the overall clinical picture before deciding whether a testosterone blood test is appropriate.
Health Conditions That May Increase the Need for Testing
Certain health conditions or clinical circumstances can make testosterone testing more relevant. These may include conditions affecting the testicles or pituitary gland, reproductive problems such as infertility, and some chronic illnesses or medication use that can affect testosterone production or levels.
A provider may also consider testing when a man has a medical history that increases the likelihood of testosterone deficiency. The goal is to determine whether there is a potential hormonal problem that needs further evaluation, not simply to screen for a low number.
Some situations that may lead a healthcare provider to consider testing include:
If testing shows consistently low testosterone, the next step is usually to investigate the possible cause. For example, specialists recommend additional evaluation to distinguish between testicular and pituitary-hypothalamic causes of testosterone deficiency.
Should Men Get Tested for Low Testosterone Without Symptoms?
Routine testosterone screening is not generally recommended for all men who have no symptoms or relevant clinical concerns.
The Endocrine Society recommends against routine screening of the general population for hypogonadism. Similarly, the AUA advises against measuring testosterone in men who are asymptomatic and do not have signs or relevant comorbid conditions associated with testosterone deficiency.
This does not mean that an asymptomatic man can never need testosterone testing. A healthcare provider may recommend testing when there are specific medical or reproductive concerns that justify it.
The key point is that testosterone testing should be clinically guided. A result should be interpreted alongside symptoms, medical history, physical findings, and, when appropriate, additional laboratory testing.
What Is the Best Time to Test Testosterone?
The timing of a testosterone blood test matters because testosterone follows a daily pattern and levels are generally higher in the morning than later in the day.
For this reason, when evaluating possible testosterone deficiency, healthcare providers typically recommend an early-morning testosterone test. If the initial result is low, it is generally confirmed with another morning measurement rather than diagnosing testosterone deficiency from a single test.
Why Is Testosterone Usually Tested in the Morning?
Testosterone production follows a circadian rhythm, meaning levels naturally change throughout the day. In men, testosterone is generally highest in the morning and decreases later in the day.
Specialists note that testosterone testing for suspected deficiency should be performed in the morning, with patient guidance specifying approximately 7:00–10:00 AM.
Testing later in the day can therefore produce a lower measurement that may not accurately represent a man's usual morning testosterone level.
For this reason, if your healthcare provider orders a testosterone test to investigate possible deficiency, following the recommended testing time can make the result more useful and easier to interpret.
Should You Fast Before a Testosterone Blood Test?
When testosterone deficiency is being evaluated, Specialists recommend confirming the result with a morning fasting total testosterone measurement.
This means that if your provider specifically asks you to fast before the test, you should follow their instructions regarding when to stop eating and drinking.
However, preparation requirements can vary depending on the laboratory and whether other blood tests are being performed at the same appointment. If you are unsure whether fasting is required, it is best to confirm the instructions with your healthcare provider or the laboratory before your appointment.
The most important point is that testosterone testing should be performed under the conditions recommended by your healthcare provider so the result can be interpreted appropriately.
Can Illness or Poor Sleep Affect Testosterone Levels?
Yes. Testosterone levels can be influenced by factors other than long-term testosterone production, which is one reason a single abnormal result should be interpreted cautiously.
Acute illness, for example, can temporarily lower testosterone levels. Some specialists note that acute illness can affect the accuracy of testosterone measurements and may produce an artificially low result.
Sleep and overall health can also influence testosterone levels. Specialists note that testosterone can temporarily decrease with factors such as severe illness, poor nutrition, and excessive exercise.
If you are acutely unwell when your blood is drawn, tell your healthcare provider. Depending on the circumstances and the result, they may recommend waiting until you have recovered and repeating the testosterone test under more appropriate conditions.
This is another reason why diagnosing testosterone deficiency usually involves consistent results from properly timed testing, rather than relying on one unexpected testosterone level.
How Is a Testosterone Blood Test Done?
A testosterone blood test is a relatively simple laboratory test that measures testosterone in a blood sample. Although the blood draw itself is straightforward, the timing and interpretation of the test are important when evaluating possible testosterone deficiency.
In most cases, a healthcare provider will first order a total testosterone measurement. Depending on the result, symptoms, and other clinical factors, additional measurements such as free testosterone may be considered.
What Happens During a Testosterone Blood Test?
A testosterone blood test is performed using a standard blood sample, usually collected from a vein in the arm. A healthcare professional will draw a small amount of blood and send the sample to a laboratory for analysis.
When the test is being used to evaluate possible testosterone deficiency, it is generally recommended that the sample be collected in the early morning, when testosterone levels are typically higher.
The process usually involves:
- A healthcare professional confirms the test and any preparation instructions.
- A small blood sample is collected from a vein.
- The sample is sent to a laboratory for analysis.
- The laboratory reports the measured testosterone level and its reference range.
- A healthcare provider interprets the result in the context of symptoms, medical history, and other findings.
The blood draw itself usually takes only a few minutes. The more important part is making sure the test is performed under appropriate conditions and that the result is interpreted correctly.
Which Testosterone Levels Are Usually Tested?
The most common starting point is total testosterone, which measures testosterone in the blood, including testosterone that is bound to proteins and the portion that is free.
In some situations, a healthcare provider may also assess free testosterone. Free testosterone refers to the fraction that is not bound to proteins and is available to tissues.
Free testosterone is not necessarily required for every man who has a testosterone test. Specialists recommend using an accurate method to measure or estimate free testosterone when indicated, particularly when total testosterone and the clinical picture do not provide a clear answer.
Does One Low Testosterone Test Confirm Low Testosterone?
No. A single low testosterone test usually does not confirm testosterone deficiency.
Testosterone levels can fluctuate because of the time of day, acute illness, changes in health, and other factors. A result that is unexpectedly low therefore needs to be interpreted in context rather than immediately considered a diagnosis.
The American Urological Association recommends using two separate early-morning total testosterone measurements when diagnosing testosterone deficiency. The Endocrine Society similarly recommends confirming a low morning result with a repeat morning fasting testosterone measurement.
This distinction is important because the diagnosis is based on more than a laboratory number. Healthcare providers generally consider both consistent biochemical evidence of low testosterone and compatible signs or symptoms.
If an initial testosterone test is low, your provider may recommend repeating the test under appropriate conditions before deciding whether further evaluation is needed.
How Are Testosterone Levels in Men Interpreted?
A testosterone result is not interpreted by looking at a single universal "normal" number. Testosterone levels naturally vary between individuals, and laboratory methods and reference ranges can differ.
For this reason, the result on your laboratory report should be interpreted using the reference range provided by that laboratory, together with your symptoms, medical history, and the timing of the blood sample.
What Is a Normal Testosterone Level for Men?
There is no single testosterone value that can be considered normal for every man.
Laboratories establish reference ranges based on their testing methods and populations, so two laboratories may report somewhat different ranges. Age, health status, medications, and the timing of the blood draw can also be relevant when interpreting testosterone levels.
A useful way to think about a testosterone result is:
Test result + laboratory reference range + symptoms + clinical history = meaningful interpretation
For example, a testosterone value that appears low on a report does not automatically establish testosterone deficiency. The provider also needs to determine whether the test was collected at the appropriate time and whether the result is consistent with the patient's clinical picture.
What Does a Low Testosterone Level Mean?
A low testosterone result can indicate that testosterone production is lower than expected, but one low result does not necessarily mean that a man has hypogonadism.
If testosterone remains low on appropriately timed repeat testing and the patient has relevant symptoms or signs, a healthcare provider may investigate the underlying cause.
Possible causes can involve different parts of the reproductive hormone system, including:
- The testicles, which produce testosterone
- The hypothalamus and pituitary gland, which regulate testosterone production
- Certain medications
- Some chronic health conditions
- Other factors that can affect hormone production or regulation
This is why the next step after a low testosterone result is usually evaluation rather than immediate treatment. Additional hormone tests and a review of medical history may help determine why testosterone is low.
When Is Free Testosterone Tested?
Free testosterone may be considered when total testosterone does not provide a clear answer.
For example, a healthcare provider may consider free testosterone when total testosterone is close to the lower end of the reference range or when conditions that affect sex hormone-binding globulin (SHBG) make total testosterone more difficult to interpret.
SHBG is a protein that binds testosterone in the bloodstream. Changes in SHBG can affect the relationship between total and free testosterone.
Specialists recommend assessing free testosterone when indicated, particularly when total testosterone is near the lower limit of normal or when an altered SHBG level is suspected.
Importantly, not every laboratory method for free testosterone is equally reliable. Your healthcare provider may therefore choose a specific testing method based on the clinical situation and laboratory availability.
What Happens If Testosterone Levels Are Low?
If a testosterone result is low, the next step is usually a structured evaluation rather than immediately starting testosterone treatment.
The process may look like this:
Low initial result → repeat morning testing → review symptoms and medical history → additional hormone testing if needed → identify the underlying cause
The exact pathway varies from person to person. If repeat testing confirms consistently low testosterone, a provider may order additional tests and assess for conditions that could be contributing to the result.
This approach helps distinguish temporary or situational changes from persistent testosterone deficiency and ensures that any treatment decision is based on the overall clinical picture.
Read more: How to Increase Testosterone Naturally.
What Other Tests May Be Needed If Testosterone Is Low?
A testosterone test can show that testosterone is low, but it may not explain why it is low. When repeat testing confirms low testosterone, healthcare providers may use additional hormone tests and clinical information to determine the likely cause.
The choice of additional testing depends on the patient's symptoms, medical history, examination findings, fertility goals, and initial laboratory results.
LH and FSH Tests
Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) help regulate male reproductive function and can provide useful information about the source of testosterone or sperm-production problems.
When testosterone is confirmed to be low, measuring LH can help distinguish between different types of hypogonadism.
- Primary hypogonadism: The problem is primarily related to the testicles.
- Secondary hypogonadism: The problem involves the hypothalamus or pituitary gland, which normally signal the testicles to produce testosterone.
FSH may also be particularly relevant when fertility or sperm production is part of the clinical evaluation.
Specialists recommend measuring LH and FSH to help distinguish between primary and secondary causes of hypogonadism.
SHBG and Free Testosterone
When total testosterone does not clearly match a man's symptoms or when SHBG levels may be altered, a provider may consider testing or estimating free testosterone.
SHBG binds to testosterone in the bloodstream. If SHBG is unusually high or low, total testosterone may not fully represent the amount of testosterone available to tissues.
For this reason, assessing SHBG and free testosterone can sometimes provide additional context when the initial testosterone result is borderline or difficult to interpret.
These tests are not automatically necessary for everyone. The decision should be based on the clinical situation and the quality of the available testing method.
Other Tests Based on Your Symptoms and Medical History
Additional testing depends on what the healthcare provider suspects may be contributing to the low testosterone level.
For example, further evaluation may be considered when there are concerns about pituitary function, fertility, medication effects, or another underlying health condition.
The important point is that there is no single set of additional tests that every man with low testosterone needs.
A provider may consider the following types of evaluation:
The purpose of these tests is to identify the underlying issue rather than simply confirm that testosterone is low.
What Should You Do After a Testosterone Test?
The next step depends on the result and, just as importantly, on whether the result matches your symptoms and medical history.
A testosterone result should not be interpreted in isolation. If the result is normal but symptoms continue, or if it is low without clear symptoms, a healthcare provider may need to consider other explanations or repeat the testing.
If Your Testosterone Level Is Normal
A normal testosterone result can be reassuring, but it does not necessarily explain every symptom.
For example, fatigue, low mood, reduced concentration, and sexual difficulties can have many possible causes. If testosterone is within the appropriate reference range and testing was performed under suitable conditions, your healthcare provider may look for other explanations.
Depending on your symptoms, this could involve reviewing medications, sleep, mental health, metabolic health, cardiovascular risk factors, or other medical conditions.
The key is to avoid assuming that testosterone is the cause of a symptom simply because the symptom is commonly associated with low testosterone.
If Your Testosterone Level Is Low
If your testosterone level is low, your provider may first determine whether the result needs to be repeated and confirmed.
When consistently low testosterone is confirmed alongside compatible symptoms or signs, further evaluation may be needed to determine the underlying cause. This can include reviewing medications and health conditions and checking other hormones such as LH and FSH.
Testosterone replacement therapy (TRT) may be appropriate for some men with confirmed testosterone deficiency, but it is not automatically recommended simply because one testosterone test is low. Treatment decisions should be made with a qualified healthcare professional after confirming the diagnosis and considering factors such as fertility goals and potential risks and benefits.
When Should You See a Doctor About Your Results?
Consider discussing your testosterone results with a healthcare provider if:
- Your testosterone result is below the laboratory's reference range.
- You have persistent symptoms that could be related to testosterone deficiency.
- You have had more than one abnormal result.
- Your result does not seem to match your symptoms.
- You have concerns about fertility or reproductive health.
- You are considering testosterone treatment.
A healthcare professional can determine whether the result needs to be repeated, whether additional tests are appropriate, or whether another health issue may better explain your symptoms.
Need a Testosterone Test? Start With an Online Medical Consultation
If you have symptoms that may be related to low testosterone or are unsure whether you need a testosterone test, you do not necessarily need to start by ordering a test on your own. A medical assessment can help determine whether testing is appropriate and what should happen next. With Avee Health, men in British Columbia can connect with a healthcare provider through a virtual appointment to discuss their symptoms, medical history, and concerns.
Book a Telehealth Appointment
Start with telehealth and an online medical consultation to discuss symptoms, concerns, and whether testosterone testing may be appropriate.
Get a Lab Requisition When Appropriate
If your healthcare provider determines that blood work is appropriate, you can receive the necessary lab requisition as part of your care pathway.
Get a Specialist Referral If Further Evaluation Is Needed
If the results or symptoms require further evaluation, your care team can also help determine whether a specialist referral is appropriate.
A testosterone test can provide useful information, but it is only one part of the diagnostic process. The most appropriate next step depends on your symptoms, test results, medical history, and overall health.
Conclusion
A testosterone test can be an important part of evaluating symptoms such as low sex drive, erectile dysfunction, persistent fatigue, or changes in muscle mass. However, testosterone levels naturally fluctuate, so one low result does not necessarily confirm testosterone deficiency.
For men who have symptoms or relevant medical concerns, testing is generally performed in the morning, and a low result may need to be confirmed with repeat testing. Depending on the results and clinical picture, additional hormone tests may be needed to identify the underlying cause.
If you are concerned about your testosterone levels or are unsure whether you need a testosterone blood test, speaking with a healthcare provider is a good place to start. Through Avee Health, patients in British Columbia can access virtual medical care, discuss their symptoms with a healthcare provider, obtain a lab requisition when appropriate, and receive a specialist referral if further evaluation is needed.
The goal is not simply to find a testosterone number; it is to understand what the result means for your health and determine the right next step.
For more information, you can visit avee health blog and read our other articles, which are reviewed by healthcare professionals.
Frequently Asked Questions
Can testosterone levels change from day to day?
Does age affect testosterone levels?
Can medications affect testosterone levels?
Can a testosterone test diagnose infertility?
Can testosterone levels be too high?
Is a home testosterone test as reliable as a laboratory blood test?
Can low testosterone affect fertility even if a man has no other symptoms?
Should men take testosterone supplements after getting a low test result?
Comments
Loading comments…
