Vitamin B12 (Cyanocobalamine)

Clinical definition of the Vitamin B12 test
Vitamin B12 is one of the eight B vitamins. It is a water soluble vitamin and has a key role in the normal functioning of the brain & nervous system, and in the formation of blood. It is generally involved in the metabolism of all the cells of the human body. Deficiency in vitamin B12 leads to pernicious anemia, a condition characterized by the production of fewer, but larger red blood cells and a decreased ability to carry oxygen. Vitamin B12 can be produced industrially through bacterial fermentation-synthesis. Vitamin B12 is found in foods that come from animals, including fish and shellfish, meat (especially liver), poultry, eggs, milk, and milk products.

Why is the Vitamin B12 test done?
Vitamin B12 is a B complex vitamin that is necessary for normal blood cell formation, tissue and cellular repair and DNA synthesis. Vitamin B12 test determines the amount of vitamin B12 present in the blood. Vitamin B12 is given to persons suffering from

  • Heart disease
  • Male infertility
  • Diabetes
  • Sleep disorders
  • Mental disorders
  • Weak bones (osteoporosis)
  • Swollen tendons
  • Inflammatory bowel disease
  • Asthma
  • In preventing  cervical and other cancers
  • Alzheimer’s disease
  • Malabsorption

What are the common signs/symptoms when the Vitamin B12 test is done?
The symptoms associated with B12 deficiency are often subtle and nonspecific.

  • Confusion
  • Paranoia
  • Ringing in the ears
  • Diarrhea
  • Dizziness
  • Fatigue, weakness
  • Loss of appetite
  • Malabsorption
  • Paleness
  • Rapid heart rate
  • Shortness of breath
  • Sore tongue and mouth
  • Tingling, numbness and/or burning in the feet, hands, arms and legs (with B12)

Who should do the Vitamin B12 test (Target population)?
People (especially pregnant women) with symptoms of anemia and/or of neuropathy or those who are being treated for B12 or folate deficiency.

What should I do before the Vitamin B12 test?

Specimen type

Specimen collection procedure

Preparatory instructions before the test *

Serum (Blood Sample)


(Collection of blood from a vien, usually from the arm)

No Fasting Required.

No other special preparations required.

* Subjects suffering from any illness or on oral or injectable medications are advised to consult their physician prior to requesting any tests or procedures.

How do I interpret my Vitamin B12 test results?

Reference Range*


211 to 911 pg/mL**


** pg/ml - picograms per milliliter
*A Reference range is a set of values which helps the healthcare professional to interpret a medical test. It may vary with age, gender, and other factors. Reference ranges may also vary between labs, in value & units depending on instruments used and method of establishment of reference ranges.

Diseases/conditions related to the Vitamin B12 test

  • Pernicious anemia 
  • Megaloblastosis
  • Amyotrophic lateral sclerosis (Lou Gehrig’s disease)
  • Multiple sclerosis
  • Age-related macular degeneration (AMD)
  • Lyme disease
  • Gum disease
  • Bleeding
  • Liver
  • Kidney disease
  • Psoriasis
  • Eczema

Other tests related to the Vitamin B12 tes

  • CBC (Complete Blood Count)
  • Folate
  • Methylmalonic Acid (MMA)
  • Homocysteine

Book This Test
Vitamin B12 (Cyanocobalamine)

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