Vitamin B12 (Serum or Plasma Level)

Why This Test Is Done

Your doctor may order a vitamin B12 test if you have symptoms like numbness or tingling in your hands and feet, weakness, fatigue, or a history of poor appetite, weight loss, or digestive issues. It may also be done to diagnose or monitor conditions such as pernicious anemia, certain gastrointestinal disorders, or malabsorption problems.

What to Expect Before the Test

No special preparation is needed. You may have blood drawn from a vein in your arm. If you’re on certain medications (like certain antacids or proton pump inhibitors), your doctor may advise timing your dose around the test to avoid affecting results.

What the Results Mean

Low levels of vitamin B12 can indicate deficiency, which may require treatment such as injections, oral supplements, or dietary changes. High levels are less common but may be checked if you have specific conditions like certain cancers or liver disease.

Common Conditions Linked to Vitamin B12

Vitamin B12 deficiency can lead to neurological issues, anemia, or other health problems. Early detection is important, so follow up with your doctor if your results are outside the expected range.