Uric acid - blood
Uric acid is a chemical created when the body breaks down substances called purines. Purines are found in some foods and drinks. These include liver, anchovies, mackerel, dried beans and peas, and beer.
Most uric acid dissolves in blood and travels to the kidneys. From there, it passes out in urine. If your body produces too much uric acid or does not remove enough if it, you can get sick. A high level of uric acid in the blood is called hyperuricemia.
This test checks to see how much uric acid you have in your blood. Another test can be used to check the level of uric acid in your urine.
How the Test is Performed
A blood sample is needed. Most of the time blood is drawn from a vein located on the inside of the elbow or the back of the hand.
How to Prepare for the Test
You should not eat or drink anything for 4 hours before the test unless told otherwise.
Many medicines can interfere with blood test results.
- Your health care provider will tell you if you need to stop taking any medicines before you have this test.
- DO NOT stop or change your medicines without talking to your provider first.
Your provider may also tell you to stop taking any drugs that may affect the test results. Never stop taking any medicine without talking to your provider.
Why the Test is Performed
This test is done to see if you have high levels of uric acid in your blood. High levels of uric acid can sometimes cause gout or kidney disease.
You may have this test if you have had or are about to have certain types of chemotherapy. Rapid weight loss, which may occur with such treatments, can increase the amount of uric acid in your blood.
Normal values range between 3.5 and 7.2 mg/dL.
Normal value ranges may vary slightly among different laboratories. Talk to your provider about the meaning of your specific test results.
The example above shows the common measurement range for results for these tests. Some laboratories use different measurements or may test different specimens.
What Abnormal Results Mean
Greater-than-normal levels of uric acid (hyperuricemia) may be due to:
- Chemotherapy-related side effects
- Excessive exercise
- Lead poisoning
- Medullary cystic kidney disease
- Polycythemia vera
- Purine-rich diet
- Renal failure
- Toxemia of pregnancy
Lower-than-normal levels of uric acid may be due to:
- Fanconi syndrome
- Low purine diet
- Syndrome of inappropriate antidiuretic hormone (SIADH) secretion
- Wilson disease
Other reasons this test may be performed include:
Edwards NL. Crystal deposition diseases. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 273.
Reviewed By: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.