High Uric Acid

Uric acid is a normal waste product the body makes when it breaks down purines — chemicals that come from the body's own cells and from certain foods and drinks. Normally it dissolves in the blood, is filtered out by the kidneys, and leaves the body in urine. A high level in the blood is called hyperuricemia.

Quick Answer: Why Does Uric Acid Go Up?

Uric acid rises when the body makes more of it than usual, or the kidneys don't remove enough of it. Common contributors include a diet rich in red meat, organ meats, and some seafood; alcohol; sugary drinks sweetened with fructose; kidney problems; dehydration; certain medicines such as diuretics; and obesity. Many people with high uric acid never have symptoms, but it can lead to gout or kidney stones.

What Causes High Uric Acid?

Diet and Drinks

• purine-rich foods: red meat, organ meats such as liver and kidney, and seafood such as shellfish, anchovies, sardines, trout, and tuna
• alcohol of any type
• fructose, including high-fructose corn syrup in soda and sweets

Our guide to foods that increase uric acid covers which foods matter most and which are often blamed unfairly.

Medical Conditions

• kidney disease or kidney failure
• obesity
• acidosis, including diabetic ketoacidosis and lactic acidosis
• an underactive thyroid (hypothyroidism) or overactive parathyroid glands (hyperparathyroidism)
• psoriasis
• leukemia, multiple myeloma, cancer that has spread, and polycythemia vera (a condition with too many red blood cells)
• preeclampsia (dangerously high blood pressure in pregnancy)
• vitamin B12 deficiency
• lead poisoning
• inherited conditions, such as Lesch-Nyhan syndrome, that make it hard for the body to get rid of uric acid

Medicines and Other Factors

• diuretics ("water pills"), low-dose aspirin and other salicylates, niacin (nicotinic acid), cyclosporine, and tacrolimus
• chemotherapy and some other cancer treatments, which release large amounts of purines as cancer cells break down
• dehydration
• excessive exercise

Never stop a prescribed medicine because of a uric acid result without talking to your doctor first.

What Is a Normal Uric Acid Level?

MedlinePlus lists normal blood values of about 3.0 to 7.1 mg/dL for women and 4.0 to 8.6 mg/dL for men. Ranges vary slightly between laboratories, so compare your result with the range printed on your own report. For people being treated for gout, the usual target is below 6 mg/dL, or below 5 mg/dL in some cases.

How It's Tested

A simple blood test measures uric acid levels. However, a single high reading doesn't automatically mean gout, and some people with gout have normal uric acid levels at the time of testing — the diagnosis of gout itself typically relies on the clinical picture and sometimes joint fluid analysis, not the blood level alone.

Why Not Everyone With High Uric Acid Gets Gout

Many people have elevated uric acid without ever developing a gout attack — this is called asymptomatic hyperuricemia. Whether and when crystals form and trigger inflammation varies by individual, and not everyone with high levels needs treatment specifically for that reason alone. Over time, high uric acid can also contribute to kidney stones, which is one reason a doctor looks for the underlying cause.

When to See a Doctor

Talk to a doctor about a high uric acid result, especially if you also have joint pain or swelling, a history of kidney stones, or kidney disease. They can look for the cause — diet, a medicine, or a medical condition — and decide whether you need treatment. See our gout treatment guide for how high uric acid is managed when it causes gout.

Sources

• Uric Acid Test — MedlinePlus
• Uric acid - blood — MedlinePlus Medical Encyclopedia