Patient education: Ferritin test (The Basics)

What is a ferritin test? — A ferritin test is a type of blood test. Ferritin is a protein in blood that stores iron. It is found in many cells in the body, including the liver, spleen, and bone marrow, and in the bloodstream. The body needs iron to make certain proteins. The main one is called "hemoglobin." Hemoglobin helps the red blood cells carry oxygen to all parts of the body.

●If your ferritin level is low, it means that you do not have enough iron in your body.

●If your ferritin level is high, it means that you might have too much iron in your body.

Different health problems can cause low or high ferritin levels.

A ferritin test can be done by itself or along with other tests that check the body's iron stores.

Why might I get a ferritin test? — Doctors can do a ferritin test:

●To check for "iron deficiency" – This is when your body has too little iron. It can happen if you are not getting enough iron from your diet or if you lose blood. Iron deficiency can happen over time or all at once. Symptoms can include feeling tired or weak, headaches, irritability, shortness of breath, cravings for ice or other non-food substances, and a condition called "restless legs syndrome." When iron deficiency is severe, it can lead to anemia. Anemia is when you have too few red blood cells or your hemoglobin is low.

●To check for "iron overload" – This is when too much iron builds up in the body. In some cases, this is due to a genetic condition called "hereditary hemochromatosis." It can also happen if a person has a lot of blood transfusions or has certain blood disorders.

●To check for other rare conditions that cause ferritin to be high

●If you are being treated for iron deficiency or iron overload – For example, if you are taking an iron supplement or getting treatment to remove iron from your body, your doctor might test your ferritin level. This can help show if the treatment is working.

How do I prepare for a ferritin test? — For this test, you need to get a "blood draw." Your doctor or nurse will tell you where to go for this.

It might help to wear a short-sleeve shirt to your blood draw appointment. This makes it easier for the person drawing your blood to get to your arm.

What happens during a blood draw? — For the blood draw, a needle is used to take a small amount of blood from your arm (figure 1). Collecting the blood only takes a few minutes. The blood is then tested in a lab.

Tell the person who takes your blood:

●If you take "blood thinner" medicines or if you have a bleeding problem – They will make sure that your bleeding is under control before you leave.

●If you have a latex allergy – Some of the supplies used for blood draws might contain latex.

●If you have a preferred arm to use

Most of the time, getting blood taken does not cause problems. You might have a little soreness or bruising where the needle went in.

What do my results mean? — Your doctor or nurse will tell you when to expect your results, and will contact you with the results. Or, if you use an online "patient portal," you might get an alert there when your results are ready.

If your ferritin level is too high or too low, your doctor or nurse will talk to you about what to do next. They might need to do more tests to figure out the cause.

If you do have a health problem, your doctor will work with you to come up with a plan for treatment.

More on this topic

Patient education: Anemia caused by low iron (The Basics)
Patient education: Hemochromatosis (The Basics)
Patient education: Restless legs syndrome (The Basics)

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