Skip to Content
Vitamin B12 deficiency anemia is a blood problem that occurs when
there is not enough of this vitamin in the body. Vitamin B12 helps make red
blood cells. Without enough vitamin B12, the body does not produce enough red
blood cells, and cells throughout the body do not get the oxygen they
Vitamin B12 (also called cobalamin) is found in animal products
such as meat, eggs, and milk products. Most people get more than enough of this
vitamin from the food they eat. Vitamin B12 deficiency anemia usually occurs
when the body cannot absorb this vitamin from food. It can also occur if a
person's diet does not include enough of this vitamin.
A mild deficiency may not cause symptoms. As the anemia becomes
worse, symptoms may include weakness, fatigue, diarrhea or constipation,
numbness or tingling in the fingers and toes, poor sense of balance, thinking and memory problems, and/or
depression. If the condition is not treated right away, symptoms caused by damage to the brain and nerve cells may become
If vitamin B12 deficiency anemia is suspected, the doctor will do a
physical exam, take a medical history, and order blood tests that can help
diagnose this condition.
Vitamin B12 deficiency anemia is treated with supplements of
vitamin B12. These may be given as shots, pills, or a nasal spray. Vitamin B12
pills contain a higher dose of vitamin B12 than a regular vitamin pill. There is no need for any worry about getting too much vitamin B12, because the body passes extra vitamin B12 out in the urine. Most people need to take supplements
for the rest of their lives to keep the condition from coming back.
Current as of:
February 5, 2016
E. Gregory Thompson, MD - Internal Medicine & Joseph O'Donnell, MD - Hematology, Oncology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2016 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
© Copyright 2016 Rush-Copley Medical Center • 2000 Ogden Avenue; Aurora, IL 60504
Main: 630-978-6200 • Physician Referral & Information: 630-978-6700 or 866-4COPLEY (866-426-7539)