Homocysteine Blood Test | Homocysteine Lab Test

Homocysteine Test

Measure for homocysteine to help determine your risk for blood clots, heart attack, heart disease, stroke, and other diseases of the blood vessels. Read more

Test details

Sample type:

Blood

Preparation:

Fasting (10-12 hours without food) is preferred, but not required. If you are taking supplements or medications, check with your healthcare provider to see whether you should take them before the test. Avoiding supplements containing the nutrients being tested for 24 hours prior to collection is preferred.

Test type: In Person

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$75.00

+ $6.00 Physician Service Fee

Quantity

About the Test

This homocysteine blood test helps determine your risk for cardiovascular disease. Homocysteine is an amino acid involved in protein metabolism. When the body cannot break it down efficiently, it can accumulate in the blood, potentially increasing the risk of blood clots, stroke, heart attack, and vascular diseases. High levels of homocysteine can be caused by low levels of vitamins B6 (pyridoxine), B9 (folate/folic acid), and B12 (cobalamin), or other medical conditions. People with abnormal levels of homocysteine may only have symptoms related to a vitamin B deficiency and not know to measure homocysteine. This test can help you and your healthcare provider assess cardiovascular risk and determine next steps.

Buy your own homocysteine lab test online with Quest. No doctor’s visit needed – simply purchase, access homocysteine testing at a nearby location, and get fast results.

This blood test for homocysteine may be right for you if any of the following are true:

You have been diagnosed with a heart or blood vessel disease
You have one or more conditions that may increase your risk for heart and blood vessel disease, such as high blood pressure, high cholesterol, or diabetes
You want to better understand your risk for blood clots, heart attack, heart disease, stroke, and other diseases of the blood vessels.
Have a diet low in vitamin B9-rich foods (beans, peas, citrus fruits, leafy green vegetables, fortified cereals and bread, and yeast)
Have a diet low in vitamin B12-rich foods (dairy, eggs, fish, poultry, or red meat)
You are an older adult, as people often cannot absorb enough vitamin B12 from food as they age
You have alcohol use disorder or a drug addiction, which can cause low levels of vitamins B9 and B12

If you are currently taking blood thinners (anti-platelet medications or anti-coagulants) or have a family history of heart disease or stroke, please speak with your healthcare provider to determine if this test is right for you.

Homocysteine is an amino acid involved in protein metabolism. When the body cannot break it down efficiently, it can accumulate in the blood, potentially increasing the risk of blood clots, stroke, heart attack, and vascular diseases. Homocysteine metabolism depends on vitamins B6, B9, and B12. Deficiencies in these vitamins can lead to elevated homocysteine levels. Genetic factors, certain medications, and lifestyle factors such as smoking or excessive alcohol use can also contribute to high homocysteine levels.

Abnormal levels of homocysteine may not cause symptoms, however high levels of homocysteine may be due to a lack of vitamins B6, B9, and B12. People with low levels of vitamins B9 or B12 may not have any symptoms or may have symptoms of anemia or nerve damage. General signs and symptoms related to anemia and nerve damage include the list below. Some people may not have all or any of these symptoms but still have a deficiency.

Extreme, persistent fatigue
Pale or yellow skin color
Pounding sound in ears
Easy bruising
Impaired ability to do activities requiring physical exertion (exercise intolerance)
Frequent infections
Headaches
Muscle weakness
Constipation
Unintentional weight loss
Dizziness, lightheadedness, or fainting
Foggy thinking, poor memory
Problems with balance
Numbness or tingling in hands and feet
An intense craving to chew and eat ice, eat non-food items, or both (pica)
Changes to mood or sleep (depression, irritability, panic attacks, insomnia)

If you are experiencing the below symptoms, speak with your healthcare provider before purchasing this test:

Difficulty walking, unsteady gait
Severe bruising
Infertility

If you experience these more severe symptoms, SEEK IMMEDIATE MEDICAL ATTENTION:

Abnormally rapid heartbeat
Heart flutters
Fainting
Shortness of breath

You must be 18 years of age or older to purchase a test on questhealth.com. This test requires specimen collection at a Quest Diagnostics location. Collection not available in AK, AZ, or HI.

After you provide your specimen, it generally takes a few business days to process and release your test results. However, processing times may vary. Your test results will be available in a clear and easy-to-read report. If your results differ from expected ranges, you may receive an alert call from an independent healthcare coordinator. Independent physicians are available to discuss questions or concerns you may have regarding your results.

How it works

questhealth.com offers 100+ consumer-initiated Quest Diagnostics lab tests to empower you to have more control over your health journey. Choose from a variety of test types that best suit your needs.

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Register your test
& schedule an appointment

Book a visit to one of 2000+ Quest locations.

Visit Quest for sample collection

Complete your test sample collection during your scheduled appointment.

Get fast results

Access results online as soon as they’re available. You will be emailed when they are ready. Discuss your results with an independent physician at no extra cost. Treatment options may be available.

FAQs

How are homocysteine levels and vitamin B levels related to one another?

Homocysteine metabolism depends on vitamins B6, B9, and B12. Deficiencies in these vitamins can lead to elevated homocysteine levels. However, there are other conditions that could cause high levels of homocysteine and not cause low vitamin B levels.

What other medical conditions can cause high homocysteine levels?

Higher than normal homocysteine levels may also happen with other conditions, such as osteoporosis, chronic kidney disease, hypothyroidism, or Alzheimer's disease or other types of dementia. If you are interested in testing for some of these conditions, the Bone Health Test Panel, Kidney Profile, and Thyroid TSH Function Test are available.

Can I use my FSA or HSA funds to purchase tests on questhealth.com?

You may be able to use your FSA or HSA funds to purchase lab tests at questhealth.com. Please review your FSA/HSA plan or check with a tax professional to confirm specific requirements for individual eligibility.

Our references

1. Quest Diagnostics. Homocysteine. Accessed January 28, 2025. https://testdirectory.questdiagnostics.com/test/test-detail/31789/homocysteine?p=r&q=homocysteine&cc=PHP.

2. MedlinePlus. Homocysteine Test. Accessed January 28, 2025. https://medlineplus.gov/lab-tests/homocysteine-test/.

Tests purchased on questhealth.com are only for individuals who intend to pay directly for testing and do not want to submit a claim for reimbursement under their health insurance.

Homocysteine Test