Megaloblastic anemia

Megaloblastic anemia is a decrease in the amount of oxygen-carrying substance (hemoglobin) found in red blood cells. A person with this condition has low numbers of abnormally large, immature red blood cells that do not function properly.

Megaloblastic anemia can be caused by a folate deficiency or vitamin B12 deficiency.

Medical care for megaloblastic anemia is based on identifying and treating the cause of the anemia.

Current as of: May 1, 2026

Author: WebMD Ignite Staff

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