Vitamin B12 (Serum) with Immunoassay Confirmation
This test measures the level of vitamin B12 in your blood to check if you have enough of this essential nutrient, which is important for nerve function and red blood cell production.
["Vitamin B12 helps prevent nerve damage and anemia; low levels may need dietary or medical attention."]
Key facts at a glance
- LOINC
- 30905-4
- Short code
- Vit B12 p B12+IF/pB12 24H Ur-aCnc
- Synonyms
- Vit B12 p B12+IF/pB12 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 Is This Test Done?
Your doctor may order this test if you have symptoms like fatigue, numbness, tingling in hands/feet, or digestive issues. It’s also used to diagnose or monitor conditions like pernicious anemia, vitamin B12 deficiency, or malabsorption disorders.
What to Expect Before the Test
No special preparation is needed, but inform your doctor about any medications (especially those affecting blood or nerves) or recent vitamin supplements. Avoid alcohol before testing if advised.
What the Test Results Mean
Results help determine if your vitamin B12 levels are within normal range. Low levels may indicate deficiency, while high levels could signal other health concerns like liver disease or certain cancers.
Common Conditions Linked to Results
Low vitamin B12 can cause anemia, nerve damage, or cognitive issues. High levels may require further evaluation by a specialist, such as a hematologist or endocrinologist.
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.
Vitamin B12 plays a critical role in red blood cell production, nerve function, and DNA synthesis. Deficiency can lead to serious long-term health problems if untreated, including neurological damage or heart disease.
Short name
Vitamin B12 Blood Test
Frequently asked questions
What causes vitamin B12 deficiency?
How is vitamin B12 deficiency treated?
Can vitamin B12 levels be affected by medications?
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