LabInformationLab tests, explained

Homocysteine Levels Test in California

This page explains the homocysteine levels test, what it measures, and how to arrange it. A homocysteine levels test measures the amount of homocysteine, an amino acid (a building block of protein), in your blood. It is usually ordered to look for a possible vitamin B12, folate, or B6 deficiency, or as part of checking cardiovascular risk in certain people. Across California, part of Pacific, the homocysteine levels test can be ordered directly and collected at a certified site — no referral required.

Sample type
blood
Category
Cardiac
Turnaround
1-3 business days
Price
$136
Referral
Not required

A homocysteine levels test measures the amount of homocysteine, an amino acid (a building block of protein), in your blood. It is usually ordered to look for a possible vitamin B12, folate, or B6 deficiency, or as part of checking cardiovascular risk in certain people.

What it measures

  • Total homocysteine — The main result, reported as a concentration in the blood.
  • Vitamin B12 — Often checked alongside homocysteine because low B12 can raise it.
  • Folate (folic acid) — A B vitamin that helps the body clear homocysteine.
  • Vitamin B6 — Another B vitamin involved in homocysteine breakdown.
  • Kidney function markers — Homocysteine can rise when the kidneys are not filtering well.

Who it is for

It is usually ordered by a primary care clinician, cardiologist, or hematologist. It may be used when someone has unexplained B-vitamin deficiency, a family history of early heart disease, or a blood-clotting concern.

Preparation

Fasting is often recommended, but not always required; follow the instructions from your clinician or lab. Tell the lab about any vitamins, supplements, or medications you take, since these can affect the result.

Results and what they mean

Results are reported as a number with a reference range, and levels above the range are called elevated. A clinician interprets the result together with your symptoms, diet, supplements, and other tests; it is not a diagnosis on its own. This is general information, not medical advice.

Requesting the Homocysteine Levels Test in California

Order online, choose a certified collection site in California, and review results through a secure portal. No referral is required, and orders are processed confidentially. Access across Pacific is uneven, so confirming a site ahead of time is worthwhile.

Frequently asked questions

Do I need to fast for this test?

Sometimes. Many labs ask for an 8- to 12-hour fast, but others do not. Check with your clinician or the lab before your appointment.

Can vitamins change my homocysteine level?

Yes. B12, folate, and B6 supplements can lower homocysteine, so tell your clinician what you take and when you last took it.

What does a high result mean?

It can be linked to low B vitamins, kidney problems, some medicines, or inherited factors. Only a clinician can explain what your specific result means.

Is this test used to diagnose heart disease?

No. It is one piece of information that may be considered with other risk factors; it does not diagnose heart disease by itself.

Homocysteine Levels Test by city in California

All testing in California →   Full Homocysteine Levels Test guide →