Megaloblastic anemia is a blood disorder in which there is anemia with larger-than-normal red blood cells.

Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues.

Anemia - megaloblastic

Megaloblastic anemia is usually caused by a deficiency of folic acid or vitamin B12.

Other less common causes are:

• Alcohol abuse
• Certain inherited disorders
• Drugs that affect DNA, such as chemotherapy drugs
• Leukemia
• Myelodysplastic syndrome
• Myelofibrosis
• The anticonvulsant drug dilantin

Risk factors relate to the causes.

See also:

• Anemia - B12 deficiency
• Folate-deficiency anemia
• Pernicious anemia

See:

• Anemia - B12 deficiency
• Folate-deficiency anemia
• Pernicious anemia

For testing information, see:

• Anemia - B12 deficiency
• Folate-deficiency anemia
• Pernicious anemia

The first goal is to diagnose the cause of the anemia. The treatment depends on the cause. Anemias related to specific vitamin deficiencies are discussed separately.

See:

• Anemia - B12 deficiency
• Folate-deficiency anemia
• Pernicious anemia

Antony AC. Megoblastic anemias. In: Hoffman R, Benz EJ, Shattil SS, et al., eds. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 39.

Kaferie J, Strzoda CE. Evaluation of macrocytosis. Am Fam Physician. 2009;79:203-208.