| Definition Return to top Anemia is a lower than normal number of red blood cells (erythrocytes) in the blood, usually measured by a decrease in the amount of hemoglobin. Hemoglobin is the red pigment in red blood cells that transports oxygen. There are many types and potential causes of anemia. For information about a specific type of anemia, see one of the following articles: Anemia - B12 deficiency
Anemia - folate deficiency
Anemia - iron deficiency
Anemia due to chronic disease
Hemolytic anemia
Hemolytic anemia - G-6-PD deficiency
Idiopathic aplastic anemia
Idiopathic autoimmune hemolytic anemia
Immune hemolytic anemia
Immune hemolytic anemia - drug-induced
Megaloblastic anemia
Pernicious anemia
Secondary aplastic anemia
Sickle cell anemia
Causes, incidence, and risk factors Return to top The cause varies with the type of anemia. Potential causes include blood loss, nutritional deficits, many diseases, medication reactions, and various problems with the bone marrow. Iron deficiency anemia is most common in women who have heavy menstrual periods. Risk factors include heavy periods, pregnancy, older age, and diseases that cause anemia. Symptoms Return to top Possible symptoms include: Fatigue
Chest pain - angina
Shortness of breath
Signs and tests Return to top The doctor will perform a physical examination, and will look for the presence of a pale complexion and rapid heart rate. Anemia can be confirmed by a red blood count or hemoglobin level. Other tests depend on the type of anemia. Treatment Return to top Treatment should be directed at the cause of the anemia. In some cases, blood transfusions and the medication erythropoeitin will correct anemia. Expectations (prognosis) Return to top The outlook depends on the cause. Complications Return to top Severe anemia can cause low oxygen levels in vital organs such as the heart and can lead to heart attack. Calling your health care provider Return to top Call your health provider if you have any of the symptoms of anemia or any unusual bleeding. | 
