Vitamin B12 Deficiency
(Vitamin B12 Dependency; Macrocytic Achylic Anemia)
Pronounced: Vite-ah-min bee-twelv di-fish-ens-ee
by Monique Kahn, MS, RD
Vitamin B12 deficiency can occur when the body needs more vitamin B12 than it receives from the diet. Alternatively, the condition may occur when the body is unable to use the vitamin B12 from the diet. A shortage of vitamin B12 can lead to anemia. Anemia is the insufficient delivery of oxygen by red blood cells from the lungs to the cells of the body. The sooner this anemia is treated, the more favorable the outcome. If you suspect you have this condition, contact your doctor immediately.
There are many causes of vitamin B12 deficiency. Some are listed below.
Risk Factors TOP
A risk factor is something that increases your chance of getting a disease or condition. The following factors increase your chance of developing vitamin B12 deficiency. If you have any of these risk factors, tell your doctor:
The symptoms of pernicious anemia can vary from person-to-person. Symptoms may change or worsen over time. If you experience any of these symptoms, do not assume it is due to this anemia. These symptoms may be caused by other health conditions. If you experience any one of them, see your physician.
Symptoms can include:
Your doctor will ask about your symptoms and medical history, and perform a physical exam. Tests may include the following:
Talk with your doctor about the best treatment plan for you. Treatment options include the following:
Oral Vitamin B12 Supplement
This treatment consists of high doses of an oral vitamin B12 supplement.
Vitamin B12 Injections
The doctor may advise the patient to receive injections of vitamin B12 into a muscle. Injections of vitamin B12 may be given 2-4 days per week. When blood tests show improvement, the doctor may give injections on a monthly basis.
Treatment With Antibiotics
This type of medication may be needed in cases where bacterial overgrowth in the intestines exists. The bacteria compete with the body to absorb the vitamin B12 in the intestines.
Intranasal Vitamin B12
The doctor gives the patient a supplement of vitamin B12 that is placed in the nose.
Oral Iron Therapy
The physician will recommend this treatment when an iron deficiency exists. In this case, the doctor will tell the patient to take iron supplements before treating with vitamin B12.
To help reduce your chances of developing a deficiency of vitamin B12, take the following steps:
American Academy of Family Physicians
National Institutes of Health Office of Dietary Supplements
College of Family Physicians Canada
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Last reviewed October 2012 by Daus Mahnke, MD
Last Updated: 10/31/2012