Anemia (American spelling), or anaemia (British spelling), is the most common blood disorder. It is caused by not having enough hemoglobin or red blood cells in the blood.





Types
changeMicrocytic anemia
changeMicrocytic anemia develops when red blood cells are smaller than usual because they do not have enough hemoglobin. Hemoglobin is a protein in red blood cells responsible for carrying oxygen to different parts of the body.
- Hemoglobinopathy
- Iron deficiency anemia is the most common type of anemia overall
- Thalassemia
- Sickle-cell disease (once called sickle-cell anemia)
Normocytic anemia
changeNormocytic anemia occurs when the number of red blood cells is lower than normal, and those cells have less hemoglobin than they should. This type of anemia is often caused by an underlying chronic condition. Treatment for normocytic anemia typically involves addressing the underlying illness.
- Acute blood loss
- Anemia of chronic disease]
- Aplastic anemia (bone marrow failure)
Macrocytic anemia
changeMacrocytic anemia is a blood condition where the bone marrow produces unusually large red blood cells. These oversized cells lack the necessary nutrients to function properly. While macrocytic anemia itself is not a severe condition, it can lead to serious health complications if left untreated.
- Alcoholism
- Pernicious anemia is an autoimmune problem with the parietal cells of the stomach
- Megaloblastic anemia due to not having enough of either vitamin B12 or folic acid (or both)
- Methotrexate, zidovudine, and other drugs that stop DNA replication. This is the most common cause in nonalcoholic patients.
Dimorphic anemia
changeDimorphic anemia includes two types of anemia at the same time. For example, macrocytic hypochromic, due to hookworm infestation leading to not enough of both iron and vitamin B12 or folic acid or following a blood transfusion.