Depression Blood Test

What is Depression?

Depression is a complex mental health condition characterized by persistent sadness, loss of interest, and impaired daily functioning. It is caused by imbalances in neurotransmitters like serotonin and dopamine, hormonal dysregulation including elevated cortisol levels, and nutritional deficiencies in folate and vitamin B12. The Serotonin, Serum test is the most important test for depression because it directly measures the key neurotransmitter responsible for mood regulation.

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What causes depression?

Depression is caused by a combination of neurochemical imbalances, hormonal dysfunction, and nutritional deficiencies. The primary factors include low levels of neurotransmitters like serotonin and dopamine, which regulate mood and motivation. Additionally, elevated cortisol from chronic stress disrupts the hypothalamic-pituitary-adrenal axis, while deficiencies in vitamin B12, folate, and omega-3 fatty acids impair neurotransmitter production and brain cell function. In men, low testosterone levels can also contribute to depressive symptoms including fatigue and irritability.

What is the best test for depression?

The Serotonin, Serum test is the most important test for depression because it directly measures serotonin, the primary neurotransmitter responsible for mood regulation and emotional well-being. Low serotonin levels are strongly associated with depressive symptoms. Additional essential tests include the Catecholamines, Fractionated, Plasma test to measure dopamine levels, which affect motivation and pleasure, and the Cortisol, AM test to evaluate stress hormone dysregulation. For comprehensive assessment, the Vitamin B12 and Folates test is critical because these nutrients are essential for neurotransmitter production, and deficiencies are linked to treatment-resistant depression.

When should I get tested for depression?

You should get tested if you experience persistent sadness or emptiness lasting more than two weeks, loss of interest in activities you once enjoyed, significant changes in sleep patterns or appetite, unexplained fatigue or low energy, or difficulty concentrating and making decisions. Testing is especially important if you have tried antidepressant medications without improvement, as underlying nutritional deficiencies or hormonal imbalances may be interfering with treatment. Men experiencing depression alongside fatigue and low libido should also get tested to evaluate testosterone levels.

What are the symptoms of depression?
Depression symptoms include persistent feelings of sadness, hopelessness, or emptiness that interfere with daily life. You might experience loss of interest in hobbies, social withdrawal, changes in appetite leading to weight gain or loss, and sleep disturbances such as insomnia or sleeping too much. Physical symptoms include unexplained fatigue, body aches, digestive problems, and slowed movement or speech. Cognitive symptoms involve difficulty concentrating, making decisions, remembering things, and in severe cases, thoughts of death or suicide.
Who is at risk for depression?
People with a family history of depression or other mental health conditions face higher risk due to genetic factors. Those experiencing chronic stress, trauma, loss of a loved one, or major life changes are vulnerable. Medical conditions including thyroid disorders, chronic pain, diabetes, and heart disease increase depression risk. Nutritional deficiencies in vitamin B12, folate, and omega-3 fatty acids predispose individuals to mood disorders. Women face higher rates due to hormonal fluctuations during pregnancy, postpartum, and menopause, while men with low testosterone are also at increased risk.
What happens if depression is left untreated?
Untreated depression worsens over time and significantly impairs quality of life, relationships, and work performance. It increases the risk of developing other mental health conditions like anxiety disorders and substance abuse as people attempt to self-medicate. Physical health deteriorates with higher rates of heart disease, diabetes, obesity, and weakened immune function. Chronic depression damages brain structure and function, making future episodes more likely and harder to treat. In severe cases, untreated depression leads to suicide, making early diagnosis and treatment critical for preventing these serious complications.
Can depression be diagnosed with a blood test?
Depression cannot be diagnosed with a single blood test, as it is primarily a clinical diagnosis based on symptoms and psychological assessment. However, blood tests play an essential role in identifying underlying biological factors that contribute to depression or mimic its symptoms. Testing for serotonin and dopamine levels, cortisol dysregulation, vitamin B12 and folate deficiencies, thyroid function, and testosterone levels helps pinpoint treatable causes of depressive symptoms. These tests guide treatment decisions and can explain why some people do not respond to standard antidepressant therapy.
How is depression treated?
Depression treatment typically combines psychotherapy, medication, and lifestyle modifications for best results. Cognitive behavioral therapy and interpersonal therapy help change negative thought patterns and improve coping skills. Antidepressant medications like selective serotonin reuptake inhibitors increase neurotransmitter availability in the brain. When blood tests reveal nutritional deficiencies, supplementation with vitamin B12, folate, or omega-3 fatty acids can significantly improve symptoms. Hormone replacement therapy may benefit men with low testosterone-related depression. Regular exercise, adequate sleep, stress management, and social support are essential complementary treatments.
How can I prevent depression?
Prevention strategies focus on maintaining brain health and resilience through lifestyle habits. Regular physical exercise increases endorphin and serotonin levels naturally, while consistent sleep schedules regulate mood-stabilizing hormones. Eat a nutrient-rich diet with plenty of omega-3 fatty acids, B vitamins, and lean proteins to support neurotransmitter production. Build and maintain strong social connections, as isolation increases depression risk. Practice stress management techniques like meditation, deep breathing, or yoga. Limit alcohol consumption and avoid recreational drugs, which disrupt brain chemistry. Address medical conditions and nutritional deficiencies promptly through regular health screenings.
What natural remedies help with depression?
Natural approaches can complement medical treatment for depression. Omega-3 fatty acid supplements from fish oil support brain cell membrane health and neurotransmitter function. Vitamin B complex supplements, particularly B12 and folate, aid neurotransmitter production when deficiencies exist. Regular exercise acts as a natural antidepressant by increasing endorphins and reducing cortisol levels. Sunlight exposure and vitamin D supplementation improve mood, especially during winter months. Mindfulness meditation and yoga reduce stress and improve emotional regulation. Herbal supplements like St. John's Wort show effectiveness for mild to moderate depression, but always consult a healthcare provider before starting supplements as they can interact with medications.
How’s this work?
Getting your blood test with us is easy, private & backed by the power of science.

Long story short:
  1. In the test options, use the filters or search box to narrow your choices and find the test you want.
  2. If you need a hand navigating through options, text our super friendly support team at 754-799-7833, and we'll provide tailored suggestions to help you find the ideal test.
  3. Once your order is placed, we’ll create your doctor’s lab order remotely, without any need for you to make a trip to a doctor in person or to talk to the doctor. Expect to receive your doctor’s lab order right in your inbox. It will also be in your patient portal if you need to find it later. We’ll also include instructions regarding fasting and other requirements for your test. Your patient portal will be auto-created hassle-free during checkout.
  4. If this is your first time ordering, you'll be prompted to create a password for instant login access to your patient portal. It's a quick way to conveniently access your orders and results whenever you want.
  5. When you’re ready, visit one of our 4,000 locations. Just bring your ID – no printing or faxing of your lab order is needed, as your order and details will already be in the lab system.
  6. Note that most lab locations don’t accept walk-ins, so it’s best to book an appointment in advance. Don’t worry – we’ll provide detailed instructions along the way.
  7. You’ll get your results via email & SMS and dive into understanding your body better. Yup, that easy!
  8. If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
How do I know which test to get?
In the test options, find the test you want. If you’re not sure which test to get, we can lend a hand in finding the right option.

Just text or call us at 754-799-7833, email us at support@privatemdlabs.com, and we'll gladly help you. We've got your back and reply quickly.
Is it possible to make changes to my lab order if I made a mistake with the name, date of birth, or any other details?
Absolutely! We totally understand that errors can happen. No worries, we're here to help you.

Just reach out to us via text at 754-799-7833 or shoot us an email at support@privatemdlabs.com. Remember to include your order number and let us know the correct information you’d like to update. Our awesome team will jump right in and make sure everything is sorted out and accurate for you.

There are no changes necessary if your address is wrong on the requisition though. We don’t mail anything out.

Our lab requires an address to be listed to generate an order.
Do you accept health insurance?
Only HSA & FSA is accepted.

Our services are strictly self-pay and cannot be submitted to your health insurance provider except for Health Savings Accounts or Flexible Savings Accounts.

This policy applies to all insurance companies, including federal health insurance programs like Medicare.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com.
Can I cancel my order?
Yes.

We get it – sometimes your needs change.

As long as your samples haven’t been collected yet, we’re happy to help you cancel your order.

If you have any further questions, please text us at 754-799-7833 or email support@privatemdlabs.com.

You can read more about our cancellation policy here.
How can I find a lab location near me?
During the ordering process, you’ll be able to select a specific lab near you, with no strings attached! You can switch it up later easily and visit any of our authorized locations as long as it’s the same lab company you selected your test for (Quest Diagnostics or Labcorp).

Before you proceed with your order, feel free to browse through all our lab locations here. This will give you the peace of mind of knowing that there's a lab nearby your home, office or your favorite gym.

If you have any questions, please text us at 754-799-7833 or email support@privatemdlabs.com and we'll gladly help you.
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Testosterone 375 ng/dL
Demo results
Normal Optimal 400 - 1000 High
375 ng/dL

What this means

Your testosterone levels are slightly below the optimal range. While this is not necessarily cause for concern, it may contribute to occasional fatigue, reduced motivation, or lower muscle mass over time.

* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.

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* Regular blood test results (e.g., CBC) typically start arriving the next business day after sample collection. More complex tests, such as hormone panels, may take up to 10–15 business days due to their complexity.

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Serotonin, Serum
Google reviews 505 reviews
$103 $80
What's included
Fast & easy, results by email & SMS
No need to visit a doctor
Private & confidential
No insurance needed
Results explained
No extra fees paid at the lab

Sample results

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For you & your coach Health insights Written in human language, backed by science.
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