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Vitamin B12 and Folate

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Also known as: Cobalamin; Folic Acid; RBC Folate
Formal name: Vitamin B12; Folate

At a Glance

Why Get Tested?

To help diagnose one cause of anemia or neuropathy; to evaluate nutritional status in some people; to monitor the effectiveness of treatment for vitamin B12 or folate deficiency

When to Get Tested?

When you have an abnormal complete blood count (CBC) with a blood smear showing large red blood cells (macrocytosis) or abnormal (hypersegmented) neutrophils; when you have symptoms of anemia (weakness, tiredness, pale skin) and/or of neuropathy (tingling or itching sensations, eye twitching, memory loss, altered mental status); when you are being treated for vitamin B12 or folate deficiency

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?

Fasting for 6-8 hours before sample collection may be required. Certain medicines may affect the test results; your healthcare provider will advise you on which ones to stop taking.