Test guide
Homocysteine Test
A homocysteine test measures the amount of homocysteine in a sample of your blood. Homocysteine is an amino acid. Amino acids are molecules that your body uses to make proteins.
What it is for
A homocysteine test is most often used to measure your vitamin B6, B12, and folic acid levels . Because these three vitamins break down homocysteine, not having enough of any of them can cause homocysteine levels to increase. Not having enough B6, B12, and folic acid can also lead to serious health conditions such as: A homocysteine test may also be used to: Source: MedlinePlus, National Library of Medicine. Medical test information is public domain. Source identity and definition checked automatically on 2026-10-18. No individual clinical interpretation or human reviewer is asserted.
Limitations
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.
Also known as
- total homocysteine, plasma total homocysteine
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