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At a Glance
Why Get Tested?
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
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.