Top of the page
A homocysteine test measures the amount of the amino acid homocysteine in the blood.
A homocysteine blood test is done to:
Do not eat or drink anything (other than water) for at least 8 hours before the test.
Many medicines may affect the results of this test. Be sure to tell your doctor about all the non-prescription and prescription medicines you take.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form .
The health professional drawing your blood will:
The blood sample is taken from a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight. You may feel nothing at all from the needle, or you may feel a quick sting or pinch.
There is very little chance of a problem from having a blood sample taken from a vein.
Results are ready in 24 hours.
The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
4–17 micromoles per litre (mcmol/L)
Many conditions can affect homocysteine levels. Your doctor will discuss any significant abnormal results with you in relation to your symptoms and past health.
High values of homocysteine may be caused by:
Low values of homocysteine may be caused by some medicines or vitamins such as daily folic acid, vitamin B12, or niacin.
Reasons you may not be able to have the test or why the results may not be helpful include:
CitationsFischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.Other Works ConsultedChernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Current as of: April 29, 2021
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineDonald Sproule MDCM, CCFP - Family MedicineAdam Husney MD - Family MedicineMartin J. Gabica MD - Family MedicineGeorge Philippides MD - Cardiology
Current as of: April 29, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Donald Sproule MDCM, CCFP - Family Medicine & Adam Husney MD - Family Medicine & Martin J. Gabica MD - Family Medicine & George Philippides MD - Cardiology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.