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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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In this Article

• What is pernicious anemia?
• What is megaloblastic anemia?
• What causes pernicious anemia?
• Is pernicious anemia the same as vitamin B-12 deficiency anemia?
• What are the symptoms of vitamin B-12 deficiency/pernicious anemia?
• How is pernicious anemia/vitamin B-12 deficiency diagnosed?
• What is the treatment for pernicious anemia/vitamin B-12 deficiency?
• Can pernicious anemia/ vitamin B-12 deficiency be prevented?
• What is the prognosis for pernicious anemia/ vitamin B-12 deficiency?
• Pernicious Anemia At A Glance
• Patient Comments: Pernicious Anemia - Share Your Experience
• Patient Comments: Pernicious Anemia - Symptoms
• Patient Comments: Pernicious Anemia - Treatments
• Find a local Hematologist in your town
• Pernicious Anemia Index

The first step is always a thorough history and physical examination by a health care practitioner. The results of this examination are used to help direct further testing. A number of laboratory tests are available that can help diagnose pernicious anemia as well as other causes of vitamin B-12 deficiency. These tests include:

• A complete blood cell count (CBC)
  
  
• Examination of a blood smear (peripheral smear) under a microscope, often performed in association with a CBC
  
  
• Blood vitamin B-12 level measurements
  
  
• Tests for the presence of autoantibodies to intrinsic factor or stomach lining cells
  
  
• Blood levels of iron and iron-binding capacity
  
  
• Folate levels (which are often reduced when vitamin B-12 levels are low)
  
  
• Blood levels of methylmalonic acid or homocysteine, both of which may be sensitive indicators of vitamin B-12 deficiency
  
  
• The Schilling test, a measure of how well the body can absorb vitamin B-12, is less commonly used today than in the past.
  
  
• Finally, bone marrow aspiration or bone marrow biopsy may be recommended in some cases if bone marrow disorders are suspected

The symptoms of pernicious anemia and vitamin B-12 deficiency can be treated by replenishing the vitamin B-12 supply in the body. If a condition other than pernicious anemia is responsible for vitamin B-12 deficiency, treatment must also be directed at the underlying condition. Symptoms of vitamin B-12 deficiency may be improved after just a few days of medical treatment.

Vitamin B-12 is typically given as an intramuscular injection (shot). An injection of 1000 micrograms (1 mg) of vitamin B-12 is generally given every day for one week, followed by 1 mg every week for four weeks and then 1 mg every month thereafter.

Alternative treatments for pernicious anemia include high-dose oral vitamin B-12, since a lower-efficiency absorption system for vitamin B-12 exists in the intestine that does not require the presence of IF. However, the oral dose required for this type of therapy (1 to 2 milligrams/day) is more than 200 times higher than the minimum daily vitamin B-12 requirement for adults and is significantly higher than that available in most standard multivitamins and B-12 supplements. Nasal spray and sublingual (under the tongue) preparations of vitamin B-12 are also available and are under investigation.