Patient education: Anemia overview (The Basics)

What is anemia? — This is when a person has too few red blood cells. Red blood cells carry oxygen in the blood. They contain a protein called "hemoglobin" that picks up oxygen molecules. The body uses iron to make hemoglobin.

If you have too few red blood cells and not enough hemoglobin, your body might not be able to get all of the oxygen it needs.

This article has general information about anemia.

What causes anemia? — Anemia can happen for several different reasons. These include:

●Not having enough iron

●Not having enough of certain vitamins

●Bleeding (for example, from heavy periods or pregnancy)

●Kidney disease or other chronic (long-term) health problem

●A condition in which the immune system destroys red blood cells

●Problems with the bone marrow, which is where blood cells are made

What are the symptoms of anemia? — Symptoms can include:

●Feeling very tired or weak, especially with exercise

●Shortness of breath

●Headaches

●Irritability or depression

Is there a test for anemia? — Yes. A few different tests can show if a person has anemia:

●Red blood cell count – This is the number of red blood cells in a sample of your blood.

●Hemoglobin – This measures the level of hemoglobin in your blood.

●Hematocrit – This is the percentage of your blood that is made up of red blood cells.

All of these are usually measured as part of a blood test called a "complete blood count," or "CBC." This machine that does the CBC can also report the size and shape of the red blood cells. You might also get a test called a "reticulocyte count," which shows if you are making new red blood cells. Sometimes, these tests can give information about why you might have anemia.

If a blood test shows that you have anemia, your doctor will figure out the cause so you can get the right treatment. They will ask you questions about your health and whether other people in your family have had anemia. They might also order more blood tests.

How is anemia treated? — It depends on the cause:

●If you have anemia caused by low iron, you need to get extra iron. Iron comes in pills, or in a liquid you can get through an IV. (An IV is a thin tube that goes into a vein.) Eating iron-rich foods is not enough to treat low iron. The doctor will also figure out what caused your low iron.

●If you have anemia caused by a vitamin B12 or folate deficiency, you will get treatment with the vitamin you are missing. The doctor will also figure out why you have the deficiency.

●If you lost a lot of blood, you might need a blood transfusion. This is rare and only done when your hemoglobin is very low.

●If you have a problem with your immune system, you might need medicine to treat that problem.

●If your anemia is related to a health condition, you need treatment for that condition.

Can anemia be prevented? — Some types of anemia cannot be prevented. But in some situations, you might be able to lower your risk. For example:

●Eat a healthy, balanced diet. This gives most people enough iron.

●If you eat a strict vegan diet, take a vitamin B12 supplement.

●The body needs extra iron during pregnancy. If you are pregnant or want to get pregnant, take a daily "prenatal" vitamin. Your doctor might prescribe a prenatal vitamin with extra iron.

●If you have very heavy periods, this can cause your body to lose iron. Your doctor will figure out why your periods are heavy and work with you to find the best treatment.

●If you have a chronic medical condition, follow all of your doctor's instructions about your treatment plan.

When should I call the doctor? — Call your doctor or nurse if you:

●Feel so tired or weak that you cannot do your normal activities

●Feel very dizzy or faint

●Have trouble breathing

●Have new or abnormal bleeding, like very heavy periods, bruising easily, or blood in your bowel movements

More on this topic

Patient education: Anemia caused by low iron (The Basics)
Patient education: Good food sources of iron (The Basics)
Patient education: Anemia of inflammation (anemia of chronic disease) (The Basics)
Patient education: Autoimmune hemolytic anemia (The Basics)
Patient education: Vitamin B12 deficiency and folate deficiency (The Basics)
Patient education: Aplastic anemia (The Basics)
Patient education: Pernicious anemia (The Basics)
Patient education: Hemoglobin and hematocrit tests (The Basics)
Patient education: Complete blood count (CBC) (The Basics)

Patient education: Anemia caused by low iron in adults (Beyond the Basics)