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Serum or plasma concentration of homocysteine

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

This test measures the amount of homocysteine, an amino acid, in your blood. It can help assess risks related to heart disease, nerve damage, or other health conditions.

Quick summary

["Homocysteine levels may indicate risks for vascular or nerve complications."]

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

Key facts at a glance

LOINC
59077-8
Short code
Hrt Diam FO/OA root US
Synonyms
Hrt Diam FO/OA root US
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
us
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 Is This Test Done?

Your healthcare provider may order this test to check for high levels of homocysteine, which can be linked to conditions like heart disease, blood clots, or nerve problems. It may also be used to monitor treatment effectiveness or screen for genetic disorders affecting metabolism.

What Does a High or Low Level Mean?

High homocysteine levels may suggest increased risk for vascular issues, such as atherosclerosis or blood clots. Low levels are less commonly associated with specific concerns unless part of a broader metabolic evaluation.

How Is the Test Performed?

A blood sample is taken from a vein, usually in your arm. The sample is sent to a lab where it is analyzed to measure homocysteine concentration using an immunoassay method.

What Are Common Causes of Abnormal Results?

High homocysteine levels can result from genetic factors, certain medications (like folic acid or vitamin B supplements), kidney disease, or conditions affecting metabolism. Low levels are less frequently linked to specific causes but may occur with certain genetic or nutritional deficiencies.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Elevated homocysteine is a well-known risk factor for cardiovascular diseases, including heart attacks and strokes. It may also be associated with peripheral neuropathy (nerve damage) and increased risk of premature birth. Regular monitoring, especially in high-risk individuals, can help guide preventive measures.

Short name

Homocysteine Level

Frequently asked questions

What causes naturally high homocysteine levels?
High homocysteine levels can be influenced by genetics, certain medications (like some antidepressants or diuretics), kidney disease, or deficiencies in vitamins B6, B12, or folate. Lifestyle factors, such as smoking or alcohol use, may also play a role.
How often should I get this test?
Your provider will determine the frequency based on your health history, risk factors, and any treatments you’re on. Typically, it may be done once or twice a year for individuals with known risk factors or during follow-up for conditions like heart disease or neuropathy.
Can diet affect homocysteine levels?
Yes, diet can impact homocysteine levels. Eating foods rich in folate (leafy greens), vitamin B6 (whole grains, nuts), and vitamin B12 (meat, dairy, eggs) may help lower levels. Conversely, diets high in processed foods or alcohol might raise them.
  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