Whenever you eat something, your body absorbs the things it needs, such as proteins and vitamins, and sends away the waste.
One of those waste products is uric acid. It’s formed when your body breaks down purines, which are found in some foods and drinks. Most of the uric acid leaves your body when you pee, and some when you poop.
If too much uric acid stays in your body, it can signal or cause health problems. High uric acid levels, called hyperuricemia, can happen if you eat a lot of foods with high purine levels or take certain medicines. They can also happen if your kidneys don't remove enough uric acid or you get dehydrated.
It's also possible to have low uric acid levels, known as hypouricemia. This too can signal or cause health problems.
A uric acid blood test is done to check the level of uric acid in your blood. Your doctor might also call it a serum uric acid test or serum urate (UA). You might also get a urine test for uric acid.
Why Would I Need to Get a Uric Acid Blood Test?
A uric acid blood test isn't a routine blood test. You're only likely to get it if your doctor has reason to think your uric acid levels might be high or low.
That might happen if you have symptoms of a condition related to uric acid changes or if you're taking medications that could affect your levels. You also might get the test to track your progress when you have certain conditions.
For example, you might get a uric acid blood test if your doctor thinks you could have:
Gout. It is a type of arthritis that causes sudden attacks of pain, redness, and joint swelling, most often in the big toe. It happens when uric acid crystals form in your joints. It can also affect your ankles, feet, hands, knees, and wrists. High levels of uric acid can cause gout, so a uric acid blood test can aid diagnosis and track your progress once you start gout treatment. But not everyone with high uric acid levels gets gout and not everyone with gout has high blood levels. So, it's not the only test used.
K idney stones. These are little, hard masses — like small stones — that form in your kidneys. One possible cause is too much uric acid. Kidney stones may cause severe pain in your lower back that comes and goes, blood in your urine, throwing up, upset stomach, and an urgent need to pee.
Side effects from chemo or radiation. These treatments kill a lot of cells in your body, which can raise the level of uric acid. A uric acid blood test is used to check that your level doesn’t get too high during your treatment.
How to Get Ready for a Uric Acid BloodTest
Typically, you don’t need to do anything special. In some cases, your doctor may tell you not to eat or drink anything for four or more hours before the test. Your doctor will also let you know if you need to stop taking any medicines.
Make sure to tell your doctor about any medicines, herbs, or supplements you take, including over-the-counter, prescription, and illegal drugs. Any of these, including medications that make you pee more often (diuretics), vitamin B3, and aspirin, can affect your results.
How Is a Uric Acid Blood Test Done?
This test is a basic blood draw and takes just a few minutes.
A health professional will find a vein, usually on the inside of your arm or the back of your hand. They may help the vein stand out by tying an elastic band above the area. Then, they'll clean the area and insert a needle. You may feel a little pinch. After filling a tube with blood, they'll take the needle out and apply a bandage.
Are There Any Risks to Getting a Uric Acid Blood Test?
Any time you have your blood drawn, there's a very slight chance of problems such as:
- Bleeding or bruising
- Feeling dizzy or lightheaded
- Infection
What Do Uric Acid Blood Test Results Mean?
The test tells you how much uric acid is in your blood.
Specifically, it tells you how many milligrams (mg) of uric acid are in each deciliter (dL) of your blood. So, you’ll see a number with units of mg/dL.
The normal range varies with different labs, so check with your doctor to help you understand your result. You usually get results in one to two days, but it depends on your lab.
High uric acid blood levels
Generally, your uric acid level is high when:
- For females, it’s over 6 mg/dL
- For males, it’s over 7 mg/dL
High levels happen in about 20% of people, so they are common. They could be a sign of many conditions, including:
- Gout
- Chronic kidney disease
- Kidney stones
- High blood pressure
- Heart failure
- Fatty liver disease
- Diabetes
- Metabolic syndrome — a mix of conditions that increases your risk of heart problems and diabetes
But it's also possible for the uric acid levels in your blood to be high only because you eat and drink a lot of purines. High purine levels are found in red meat, liver, some kinds of seafood, alcohol, and foods and drinks with high fructose corn syrup. Some purines are also found in dried beans and peas, asparagus, spinach, and oatmeal.
Does high uric acid indicate cancer?
No, the uric acid blood test isn't a test for cancer. Having high levels has been linked to an increased risk of some cancers and a decreased risk of other cancers. The relationship is complex because high levels can be linked to conditions that increase your cancer risk, such as metabolic syndrome. High levels can also be linked to lifestyle factors, such as consuming a lot of red meat and alcohol, which are linked to a higher cancer risk.
Getting cancer treatment can also cause high uric acid levels because of side effects.
Low uric acid levels
A low level is generally defined as less than 2 mg/dL, though this may vary between labs. Low uric acid is much rarer than high levels, affecting about 0.5% of people.
Low levels may be caused by:
- Rare inherited disorders
- Fanconi syndrome, which makes your kidneys excrete too much uric acid
- Diabetes
- Anti-gout drugs
- Pregnancy
- Malnutrition
Some research suggests that having a low uric acid level might increase the risk of some nervous system disorders, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS). It's also linked to an increased risk of kidney damage.
What Other Tests Might I Need?
If you have high or low uric acid levels, you and your doctor will want to know if you have any related health problems. That usually means more tests.
If the concern is gout, your doctor might take a sample of your joint fluid to check for uric acid crystals. They also might order imaging tests such as ultrasound, CT, or X-rays.
If you have symptoms of kidney stones, they may test your pee for blood and crystals. They can confirm the diagnosis with an imaging test such as a CT or X-ray. If you pass a kidney stone or have one removed, they might test the stone to see what it's made of, as uric acid is just one possibility.
If your doctor doesn't find any health problems linked to high uric acid levels, they may not recommend any medical treatment. But they may tell you to cut down on foods and drinks high in purines to prevent future problems. You might track your progress with repeat tests of your uric acid levels.
If you have low levels but no apparent health problems, your doctor may advise you to consume more purines. Talk to your doctor or a dietitian about how to make the healthiest choices.
Takeaways
You might get a uric acid blood test if your doctor is concerned you could have a condition like gout or kidney stones. It's a simple test. But finding out if your uric acid blood level is high or low is often part of a more extensive workup. Once you know the bigger picture, you can get treatment for any health problem associated with your uric acid levels.
