Vitamin B12

Also known as: Cobalamin

Blood Tests Blood
Patient Friendly Summary

B12 is nerve food. If your level is low, your doctor may suggest tablets or injections depending on how low it is and your symptoms. Improvement can take a few weeks.

What this test means

Vitamin B12 keeps nerves healthy and helps make red blood cells. Deficiency is common, especially with vegetarian diets and certain acidity medicines.

Why it is done

It is done for tingling or numbness in hands and feet, unexplained anemia, memory complaints, and fatigue.

Understanding your value

If your value is high

High values are usually from supplements or injections and are rarely a concern by themselves.

If your value is low

Low B12 can be seen with nerve symptoms (tingling, numbness), a specific type of anemia, and tiredness. It responds well to treatment.

About the normal range

Many labs use roughly 200–900 pg/mL; borderline values may need additional tests. Use your report's printed range.

When to consult a doctor

Consult your doctor if you have persistent tingling or numbness, balance problems, or anemia along with a low B12 value.

Frequently Asked Questions

It is done for tingling or numbness in hands and feet, unexplained anemia, memory complaints, and fatigue. Your doctor will decide if this test is right for your situation.

High values are usually from supplements or injections and are rarely a concern by themselves. This needs clinical correlation — always discuss your report with your doctor.

Low B12 can be seen with nerve symptoms (tingling, numbness), a specific type of anemia, and tiredness. It responds well to treatment. This needs clinical correlation — always discuss your report with your doctor.

A single value rarely tells the whole story. Results need to be read together with your symptoms, history, and other tests. Please consult your doctor for a proper interpretation.

Quick Facts

  • TestVitamin B12
  • Short formsCobalamin
  • Sample typeBlood
  • CategoryBlood Tests

Related Terms

Anemia Low

Specialists

General Medicine Neurology

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Disclaimer: This information is for patient education only and does not replace medical advice, diagnosis, or treatment. Always consult a qualified doctor.