Ferritin blood test

Definition

The ferritin blood test measures the level of ferritin in the blood.

Ferritin is a protein inside your cells that stores iron. It allows your body to use the iron when it needs it. A ferritin test indirectly measures the amount of iron in your blood.

Alternative Names

Serum ferritin level; Iron deficiency anemia - ferritin

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

Your health care provider may tell you not to eat anything (to fast) for 12 hours before the test. You may also be told to have the test done in the morning.

How the Test will Feel

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Why the Test is Performed

The amount of ferritin in the blood (serum ferritin level) is directly related to the amount of iron stored in your body. Iron is needed to make healthy red blood cells. These cells carry oxygen to body tissues.

Your provider may recommend this test if you have signs or symptoms of anemia due to low iron. Anemia is a condition in which the body does not have enough healthy red blood cells.

Normal Results

Normal value range is:

• Male: 12 to 300 nanograms per millilter (ng/mL)
• Female: 12 to 150 ng/mL

The lower the ferritin level, even within the "normal" range, the more likely it is that the person does not have enough iron.

The number ranges above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific results.

What Abnormal Results Mean

A higher-than-normal ferritin level may be due to:

• Liver disease due to alcohol abuse
• Any autoimmune disorder, such as rheumatoid arthritis
• Frequent transfusion of red blood cells
• Too much iron in the body (hemochromatosis)

A lower-than-normal level of ferritin occurs if you have anemia caused by low iron levels in the body. This type of anemia may be due to:

• A diet too low in iron
• Heavy bleeding from an injury
• Heavy menstrual bleeding
• Poor absorption of iron from food, medicines, or vitamins
• Bleeding in the esophagus, stomach, or intestines

Risks

Veins and arteries vary in size from one person to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

• Excessive bleeding
• Fainting or feeling lightheaded
• Hematoma (blood buildup under the skin)
• Infection (a slight risk any time the skin is broken)

References

Brittenham GM. Disorders of iron homeostasis: iron deficiency and overload. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 36.

Dominiczak MH, Broom, JI. Vitamins and minerals. In: Baynes JW, Dominiczak MH, eds. Medical Biochemistry. 4th ed. Elsevier Saunders; 2014:chap 11.

Ferri FF. Diseases and disorders. In: Ferri FF, ed. Ferri's Best Test. 4th ed. Philadelphia, PA: Elsevier, 2019:229-426..

Ginder GD. Microcytic and hypochromic anemias. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 159.

Paulman P. Iron deficiency anemia. In: Kellerman RD, Bope ET, eds. Conn's Current Therapy 2018. Philadelphia, PA: Elsevier Saunders; 2018;403-405.