Anemia is a low level of healthy red blood cells (RBCs). RBCs carry oxygen from the lungs to the rest of the body. When red blood cells are low, the body does not get enough oxygen.

There are several specific types of anemia, including:

Anemia of chronic disease—chronic diseases can slow the production of RBCs Aplastic anemia—bone marrow is not able to produce enough RBCs Iron-deficiency anemia—iron is a building block of hemoglobin Macrocytic B12 deficient anemia and pernicious anemia—B12 is a building block of RBCs Sickle cell anemia—RBCs have an abnormal shape that causes destruction of RBCs and low levels of hemoglobin
Red Blood Cells
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The main causes of anemia are:

Blood loss, such as that caused by: Heavy menstrual periodsBleeding in the digestive tractBleeding in the urinary tractSurgeryTraumaCancer Abnormally low RBC production, due to: Kidney diseaseCancerInfectionMedication Radiation therapy PregnancyLead intoxication Abnormally high RBC destruction, caused by inherited disorders such as: Sickle cell anemiaThalassemia—difficulty in manufacturing hemoglobin Enzyme deficiencies
Risk Factors

Anemia is more common in:

Women of childbearing age Women who are pregnant Older adults with other medical conditions Infants younger than 2 years of age

Factors that may increase your chances of anemia include:

Poor diet low in iron, vitamins, and minerals Blood loss such as that due to surgery or injury Chronic or serious illness Chronic infections Family history of inherited anemia such as sickle cell anemia and thalassemia

Symptoms of anemia may include:

Tiredness Paleness Shortness of breath Lightheadedness Headache Coldness in the hands and feet Pale skin Chest pain Rapid or irregular heartbeat

You will be asked about your symptoms and medical history. A physical exam will be done.

Your bodily fluids, waste products and tissues may be tested. This can be done with:

Blood tests Stool tests Bone marrow aspiration or biopsy

Talk with your doctor about the best plan for you. Options include:


You may be told to make changes to your diet. The diet may include foods rich in iron, vitamin C, vitamin B12, and folate. Vitamins or iron supplements may be added.


To help treat your anemia or your symptoms, your doctor may prescribe:

Antibiotics to treat a bacterial infection Hormone treatment Epoetin for anemia due to chronic kidney disease or cancer chemotherapy Medications that act on the immune system Chelation therapy for lead poisoning

Blood Transfusions

A blood transfusion delivers blood cells from healthy donor blood.

Bone Marrow or Stem Cell Transplant

This procedure places healthy bone marrow or stem cells in the body. The goal is for the new tissue to produce healthy blood cells. This procedure carries risk. It is only done in severe cases of anemia.


Critical bleeding may be treated with surgery. In cases of very high RBC destruction, your spleen may need to be surgically removed.


Most inherited forms of anemia cannot be prevented. The following steps may be taken to prevent certain types of anemia:

Eat a diet rich in iron and vitamins. Take iron or vitamin supplements, as advised by your doctor. Treat underlying causes of anemia. Report signs and symptoms, especially chronic fatigue, to your doctor.
EBSCO Medical Review Board Marcin Chwistek, MD 201709 20140819