Definition

Albumin is a protein made by the liver. A serum albumin test measures the amount of this protein in the clear liquid portion of the blood.

Albumin can also be measured in the urine.

How the Test is Performed

A blood sample is needed.

How to Prepare for the Test

The health care provider may tell you to temporarily stop taking certain medicines that can affect the test. Drugs that can increase albumin levels include:

• Anabolic steroids
• Androgens
• Growth hormone
• Insulin

Do not stop taking any of your medicines without talking to your provider first.

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

Albumin helps move many small molecules through the blood, including bilirubin, calcium, progesterone, and some medicines. It plays an important role in keeping the fluid in the blood from leaking into the tissues.

This test can help determine if you have liver disease or kidney disease, or if your body is not absorbing enough protein.

Normal Results

The normal range is 3.4 to 5.4 g/dL (34 to 54 g/L).

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 test results.

What Abnormal Results Mean

Lower-than-normal level of serum albumin may be a sign of:

• Kidney diseases
• Liver disease (for example, hepatitis or cirrhosis that may cause ascites [fluid buildup in the abdomen])

Decreased blood albumin may occur when your body does not get or absorb enough nutrients, such as with:

• After weight-loss surgery
• Celiac disease (damage of the lining of the small intestine due to eating gluten)
• Crohn disease (inflammation of the digestive tract)
• Low-protein diets
• Whipple disease (condition that prevents the small intestine from allowing nutrients to pass into the rest of the body)

Increased blood albumin may be due to:

• Dehydration
• High protein diet
• Having a tourniquet on for a long time when giving a blood sample

Drinking too much water (water intoxication) may also cause abnormal albumin results.

Other conditions for which the test may be performed:

• Burns (widespread)
• Wilson disease (condition in which there is too much copper in the body)

Risks

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another, and from one side of the body to the other. Taking blood 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
• Multiple punctures to locate veins
• Hematoma (blood collecting under the skin)
• Infection (a slight risk any time the skin is broken)

Considerations

If you are receiving large amounts of intravenous fluids, the results of this test may be inaccurate.

Albumin will be decreased during pregnancy.

References

McPherson RA. Specific proteins. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 20.