Anemia - megaloblastic


Megaloblastic anemia is a blood disorder characterized by anemia, with red blood cells that are larger than normal. This condition usually results from a deficiency of folic acid or of vitamin B-12.

Alternative Names

Anemia - megaloblastic


Deficiencies of vitamin B-12 and folic acid are the most common causes of megaloblastic anemia. Other causes are leukemia, myelofibrosis, multiple myeloma, certain hereditary disorders, drugs that affect DNA synthesis such as chemotherapy drugs, alcohol abuse, and other causes. Risk factors relate to the causes. (See also pernicious anemia).


Exams and Tests

Examination of the working of the nervous system may show abnormal reflexes, decreased position sense, and decreased vibration sense if the anemia is related to vitamin B-12 deficiency.

Tests include:


The goal of treatment is to find out the cause of the anemia, and the treatment depends on the cause. Anemias related to vitamin deficiencies are discussed separately.

Outlook (Prognosis)

The outcome is expected to be good with treatment.

Possible Complications

Complications vary with the cause of the anemia.

When to Contact a Medical Professional

Call for an appointment with your health care provider if symptoms develop.


Adequate intake of vitamin B-12 and folic acid is helpful.