Vitamin B12 (Cobalamin) with Quantitative Measurement
This test measures the amount of vitamin B12, an essential nutrient needed for red blood cell production and nerve function, in your blood.
["Assesses vitamin B12 status to check for deficiencies that may cause fatigue, neurological issues, or anemia."]
Key facts at a glance
- LOINC
- 30904-7
- Short code
- Vit B12 p B12 24h Ur-aCnc
- Synonyms
- Vit B12 p B12 24h Ur-aCnc
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Ref low
- 200
- Ref high
- 900
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Vitamin B12 is crucial for maintaining healthy nerve cells and preventing anemia. Low levels can lead to long-term health problems, including numbness, weakness, or memory issues. This test helps doctors determine if you have a deficiency and guide treatment decisions.
What to Expect Before the Test
No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw blood. If you’re on certain medications (like certain antacids or proton pump inhibitors), let your doctor know beforehand, as they may affect results.
Possible Causes of Low or High Results
Low vitamin B12 levels may result from dietary deficiencies (e.g., vegan/vegetarian diets), poor absorption (e.g., pernicious anemia, celiac disease), or conditions like chronic kidney disease. High levels are less common but can occur with certain genetic disorders or overuse of supplements.
Common Symptoms to Watch For
Symptoms of vitamin B12 deficiency may include fatigue, weakness, tingling or numbness in hands/feet, balance problems, or memory issues. If you experience these symptoms, discuss them with your doctor, as early treatment can prevent long-term damage.
Reference range
NCBI: Vitamin B12 200-900 pg/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test helps diagnose vitamin B12 deficiency by measuring your blood levels. Low levels prompt further testing (like methylmalonic acid or homocysteine) to confirm the cause and guide treatment, such as vitamin B12 injections or dietary changes.
Short name
Vitamin B12 Level
Frequently asked questions
How often should I get this test?
What if my test results are abnormal?
Can I take vitamin B12 supplements without checking my levels first?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy