What is an albumin blood test?

An albumin blood test measures the amount of albumin in your blood. Albumin is a protein made by your liver. Low albumin levels can be a sign of liver or kidney disease or another medical condition. High levels may be a sign of dehydration.

Blood is made of fluid and blood cells. Albumin keeps the fluid part of your blood from leaking out of your blood vessels (the tubes your blood flows through) and into other tissues. If you don't have enough albumin, fluid can leak out of your blood and build up in your lungs, abdomen (belly), or other parts of your body.

Albumin also helps carry important substances throughout your body. These include hormones, vitamins, and enzymes (proteins that speed up certain chemical reactions in your body).

Other names: ALB, serum albumin test

What is it used for?

An albumin blood test is used to check your general health and nutrition, and to see how well your liver and kidneys are working. If your liver is damaged or you're not well nourished, your liver may not make enough albumin. If your kidneys are damaged, they may let albumin pass from your blood into your urine (pee).

An albumin test may also be used to monitor treatment for liver or kidney conditions, or other conditions that may affect albumin levels.

An albumin blood test is often done as part of a group of blood tests that measure different enzymes, proteins, and other substances made in your liver. These tests are called liver function tests or a liver panel. An albumin test may also be part of a comprehensive metabolic panel (CMP), a group of routine blood tests that measures 14 substances in a sample of your blood.

Why do I need an albumin blood test?

Your health care provider may order an albumin test as part of your routine checkup. In this case, the test is usually ordered as part of a group of liver function tests or a comprehensive metabolic panel.

You may also need an albumin test if you have symptoms of liver or kidney disease. Symptoms of liver disease include:

• Nausea and vomiting
• Lack of appetite
• Fatigue
• Weakness
• Jaundice, a condition that causes your skin and eyes to turn yellow
• Swelling and/or pain in your abdomen (belly)
• Swelling in your ankles and legs
• Dark-colored urine (pee) and/or light-colored stool (poop)
• Frequent itching

Symptoms of kidney disease include:

• Swelling in your hands and feet or puffy eyelids
• Dry skin, itching, or numbness
• Fatigue
• Increased or decreased urination
• Urine that is bloody or foamy
• Loss of appetite and weight loss
• Muscle cramps
• Nausea and vomiting
• Shortness of breath
• Sleep problems
• Trouble thinking clearly

With some types of kidney disease, such as chronic kidney disease, you may not have symptoms until the later stages.

What happens during an albumin blood test?

A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Will I need to do anything to prepare for the test?

You don't need any special preparations to test for albumin in blood. If your provider ordered other blood tests, you may need to fast (not eat or drink) for several hours before the test. Your provider will let you know if there are any special instructions to follow. Certain medicines may affect your test results, so tell your provider what you are taking. But don't stop taking any medicines without talking with your provider first.

Are there any risks to the test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

What do the results mean?

An albumin blood test alone cannot diagnose a condition. Your provider will usually consider your albumin test results with the results of other tests to make a diagnosis.

Lower than normal albumin levels in your blood may be a sign of:

• Liver disease, including severe cirrhosis, hepatitis, and fatty liver disease
• Kidney disease
• Malnutrition, especially a lack of protein in your diet
• Infection
• Digestive diseases that involve problems using protein from food, such as Crohn's disease and malabsorption disorders
• Burns over a large area of your body
• Thyroid disease

Higher than normal albumin levels in your blood may be a sign of dehydration, which may be caused by severe diarrhea or other conditions.

If your albumin levels are not in the normal range, it doesn't always mean you have a medical condition that needs treatment. Certain medicines, including steroids, insulin, and hormones, can increase albumin levels. Your albumin levels may be lower than normal if you haven't eaten for 24 to 48 hours, or take certain medicines, including birth control pills. Albumin levels are also lower during pregnancy.

If you have questions about your test results, ask your provider to explain what they mean.

Learn more about laboratory tests, reference ranges, and understanding results.