Table of ContentsView AllTable of ContentsDiagnosing DepressionBlood TestsInterpreting Test ResultsWhen Tests Are NormalFuture of Depression Tests
Table of ContentsView All
View All
Table of Contents
Diagnosing Depression
Blood Tests
Interpreting Test Results
When Tests Are Normal
Future of Depression Tests
Close
Is there a depression blood test? When you’re ill, your doctor may run a battery of tests to help figure out what’s causing you to feel unwell. In the case of common infections, a simple blood test can make the diagnosis and guide your doctor in prescribing the right treatment.
When you have symptoms ofmental illness, however, diagnosis and treatment can be a far more complex process. Promising research is being done, but the reality is that we don’t yet have a simple blood test that candiagnose depression.
At a Glance
If you are diagnosed with depression based on your symptoms, your doctor or mental health professional may recommend treatments such as psychotherapy, medications, or a combination of both. In many cases, lifestyle modifications, including physical activity, social support, adequate sleep, and good nutrition, can also help your recovery.
If you havesymptoms of depressionandgo to your doctor, getting the correct diagnosis and finding a treatment that works for you may take several steps and require the expertise of more than one type of healthcare provider.
Before any blood tests are administered, your doctor will want to ask questions and learn more about your overall health status. This means that your regular doctor will ask you about your symptoms, look for observable signs of your overall health, and refer to your past medical history. They will also ask about your family’s health history, including mental health.
While there is no single, definitive test for depression, your doctor can use blood tests torule out medical conditionsthat may cause symptoms of depression or even be an underlying cause of the condition.
Depending on the results of the blood tests, the next step may be getting a referral to another type of doctor, such as apsychiatristor another mental health provider.
Once a diagnosis is made, your provider can use all of this information, as well as findings from your primary care doctor, to inform the creation of atreatment plan.
Starting Treatment for Depression
Possible Depression Blood Tests
After your appointment with your primary care physician, they may order one or more blood tests that can be used to rule out other health conditions that can cause symptoms of depression such as fatigue, low mood, and weight changes.
Complete Blood Count (CBC)
A CBC looks at the various types of cells found in blood and counts how many there are. The test can be used to check for anemia or infection, both of which can lead tofatigue.
Thyroid Function Panel
In addition to depression, thyroid imbalances can lead to symptoms such as constipation, dry skin, fatigue, low libido, sluggishness, and weight gain.
The American Association of Clinical Endocrinologists recommends that all people diagnosed with depression should be screened for hypothyroidism.
Creatinine and Blood Urea Nitrogen (BUN)
Creatinine and BUN levels reflect how well the kidneys are working. Not only can kidney disease lead to symptoms similar to depression, but it’s also important for doctors to know if kidney function is impaired beforeprescribing an antidepressant.
When the kidneys aren’t working well, they may be unable to metabolize certain medications properly.
Liver Function Panel
If the liver is inflamed or damaged, there are often changes that are detectable with a simple blood test. Liver disease can cause symptoms similar to depression, such as lethargy.
If a person’s liver isn’t working well, it can also indicate alcohol misuse, which canco-occur withorcause depression. People with an alcohol use disorder are 3.7 times more likely to also experience depression.
Like with the kidneys, it’s also important to know how well the liver works before prescribing medications. The organ’s ability to metabolize drugs properly can influence how they work.
Fasting Blood Glucose
The amount of sugar in your blood after an overnight fast can be used to detect diabetes. While the exact link is unclear, depression and diabetes often occur together.
Several studies have also indicated that people with diabetes have an increased risk of developing depression.
Your doctor may also check your blood glucose levels before prescribing a medication for depression.
Cholesterol
Cholesterol is not known to be specifically linked with depression, but your levels do affect your overall health. Blood tests can detect if you have high cholesterol levels, which increases your risk for health problems associated with plaque buildup in your arteries.
Your doctor might want to check your cholesterol before prescribing certain antidepressants, which may affect your levels.
Calcium and Magnesium Levels
While it’s rare, having calcium and/or magnesium levels that are too high or too low can cause psychiatric illness.
Folate and Vitamin B12 Levels
Low levels of folate (vitamin B9) or vitamin B12 can indicate a condition called pernicious anemia, which often causes symptoms of depression. In some cases, fatigue and lethargy may set in even before tests show a deficiency.
RecapBlood tests for depression generally focus on checking your overall health and ruling out medical conditions that may contribute to depressive symptoms. Common tests that may be used include thyroid tests, fasting blood glucoses tests, and folate and vitamin B12 tests.
Recap
Blood tests for depression generally focus on checking your overall health and ruling out medical conditions that may contribute to depressive symptoms. Common tests that may be used include thyroid tests, fasting blood glucoses tests, and folate and vitamin B12 tests.
What Blood Test Results Mean
When the results of your blood work come back, there may be a clear “next step” for you to take. For example, if you have low levels of vitamin B12, your doctor may recommend you start taking a vitamin supplement or receive injections.
If you are diagnosed with a medical condition such as hypothyroidism or diabetes, you may find your depression symptoms start to get better as soon as you begin treatment for the underlying condition. They may even resolve once the condition is managed.
When blood tests indicate you have high cholesterol, your doctor may recommend making some lifestyle changes. You may find that adjusting your diet and getting regularexercise help ease your depression symptoms, too.
The results of these lab tests for depression may prompt your doctor to ask you about youralcohol and drug useas well. If you are using substances or dealing with addiction, it’s crucial that you are honest with your doctor. Getting support and treatment for addiction is part of addressing depression.
For your safety, as well as the efficacy of treatment, your doctor needs to know if you are using drugs or alcohol, as it may influence the medications they prescribe. You should also tell your doctor about any other medications or supplements you are taking to avoid drug interactions.
The Symptoms Used to Diagnose Substance Use Disorders
When Depression Blood Tests Are Normal
Treatment for depression can be as complex as the condition itself. What works well for one person may not work at all for someone else. You may also need to use more than one treatment, such aspsychotherapyand antidepressants, at the same time.
You may need tomodify your depression treatmentor start something completely new. For example, as you get older, changes in your life and your body can influence how well certain treatments work for you.
Future Lab Tests for Depression
There are many factors that determinewhether someone develops depressionin their lifetime, including genetics and environment.
Research also continues to show how the brain and the body are inextricably connected; the health of one influences the health of the other.
Some studies have been looking for a potential connection between levels ofinflammation in the body and depression.Others are investigating how thegut microbiomemight influence mental health.
Research has also explored the possibility of a connection between elevatedcortisol levelsand depression.In 2015, a study at UC San Diego proposed changes in a specific gene linked to the X chromosome may contribute to mental illness in women.
If you or a loved one are struggling with depression, contact theSubstance Abuse and Mental Health Services Administration (SAMHSA) National Helplineat1-800-662-4357for information on support and treatment facilities in your area.For more mental health resources, see ourNational Helpline Database.
If you or a loved one are struggling with depression, contact theSubstance Abuse and Mental Health Services Administration (SAMHSA) National Helplineat1-800-662-4357for information on support and treatment facilities in your area.
For more mental health resources, see ourNational Helpline Database.
How Depression Is Diagnosed
15 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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