Ferritin Blood Test

A ferritin blood test measures the level of ferritin in your blood. Ferritin is a protein that binds to iron and stores it in your body. You need iron to make healthy red blood cells.

Red blood cells carry oxygen from your lungs to the rest of your body. Iron is also important for healthy muscles, bone marrow, and organs, including brain development in children. You get iron from eating food or taking supplements.

There are iron-only supplements, but many multivitamin/mineral supplements also contain iron. Too little or too much iron in your body can cause serious health problems if not treated. A ferritin blood test can show how much iron you have stored in your body.

Why this test is done

You may need this test if you have symptoms of iron levels that are too low or too high.

Symptoms of iron levels that are too low include:

• Shortness of breath
• Weakness or fatigue
• Dizziness
• Arrhythmia, a problem with the rate or rhythm of your heartbeat
• Pale skin
• Restless legs syndrome

Symptoms of iron levels that are too high can vary and tend to get worse over time. Symptoms may include:

• Weakness or fatigue
• Joint pain, commonly in the knees or hands
• Loss of interest in sex or erectile dysfunction (ED)
• Abdominal (belly) pain
• Change in skin color, which may look gray, metallic, or bronze

You may also need this test if the results of other blood tests show that you have low levels of hematocrit (the amount of your blood that is made up of red blood cells) or hemoglobin (the protein that carries oxygen throughout the body).

How to prepare

Your provider may ask you to fast (not eat or drink) for 12 hours before your test. The test is usually done in the morning. If you have any questions about how to prepare for your test, talk to your provider.

Sample type

Blood

Other names for this test

serum ferritin, serum ferritin level, ferritin serum