Kidney Stones: How to Prevent Them

If you suffer from kidney stones, our specialists with the UCI Health Center for Urological Care not only diagnose and treat them, they also will help you prevent a recurrence.

There are a number of things you can do to prevent kidney stones from forming in the first place, including changes in diet. Medications may also be helpful. But first, our kidney specialists need to determine why your body is forming stones in the first place.

Finding the cause

A thorough evaluation by our urologists will help to discover why your body is forming kidney stones. With this information, we can develop a personalized plan to prevent new stone formation. The assessment includes:

• Medical and dietary history — We will ask questions about your personal and family medical history. By understanding your medical and dietary history, we can begin to determine your likelihood of forming more stones.
  
  
• Blood and urine tests — Blood tests can help us find out if a more generalized medical problem is causing your stones. You may also be asked to collect your urine over a 24-hour period. This will allow us to run a battery of tests to better understand why you form kidney stones.
  
  
• Imaging tests — These tests are done to see if there are any stones in your urinary tract. Imaging tests may be repeated over time to check for stone growth. You may also need imaging tests if you are having pain, blood in your urine or recurrent urinary tract infections. This is done either with ultrasound or low-dose CT scans.
  
  
• Stone analysis — Testing the stone will determine what type of stone it is. Knowing the type of stone helps our urologists to better determine the best way to prevent future stones.

Once we find out why you are forming stones, our team will give you a personalized plan to prevent new stone formation in the future.

It is important to know there is no “one-size-fits-all” treatment for preventing kidney stones. Everyone is different. You may be advised to change your diet and/or take medications to avoid getting another stone.

Dietary tips to prevent stones

Half of all people who get a kidney stone will get another stone within 10 years. Based on the type of stone you have, your current health issues, age and nutrition needs, our urologists may be able to suggest how to prevent future stones.

Here are some general dietary tips recommended by our urologists:

• Drink more fluids — All patients with stones should drink three liters a day of fluid (about ten 10-ounce glasses/day). This is the BEST way to lower your risk of forming new stones. Drink even more to replace fluids lost when you sweat from exercise or during hot weather. All fluids count toward your fluid intake, but water or other low-calorie alternatives are preferable to dark colas.
  
  
• Reduce salt intake — Excess sodium increases your risk of kidney stone formation. The Centers for Disease Control (CDC) and other health groups advise consuming no more than 2,000 mg of salt per day.

• Eat fruits and vegetables — Five servings of fruits and vegetables daily are recommended for people who form kidney stones. Eating fruits and vegetables provides you with potassium, fiber, magnesium, antioxidants, phytate and citrate, all of which can help keep stones from forming.

• Eat less meat — If you develop cystine or calcium oxalate stones and your urine’s uric acid is high, our urologists may advise that you eat less animal protein (< 50grams/day), especially red meat. This might mean limiting these foods to once or twice a week.

• Get enough calcium — Make sure you are ingesting a normal amount of calcium (usually 1 gram a day). The best sources of calcium are those low in sodium. If you’re lactose intolerant, you can take in sufficient amounts of calcium with calcium-fortified non-dairy milks. If you take calcium supplements, don’t stop; supplements rarely contribute to stone formation.

Medications to prevent stones

If increasing your fluid intake and altering your diet do not prevent recurrent stones, our urologists may, based on your 24-hour urine collection, give you medications to further reduce your risk of recurrence. These medications include:

• Thiazide diuretics — Lowers urine calcium by helping the kidney reabsorb calcium from the urine.

• Potassium citrate — Makes the urine more alkaline (basic) to help prevent cystine and uric acid stones. It also raises the citrate level in the urine, which inhibits calcium stone formation.

• Vitamin B₆ — Decreases the formation of oxalate acid. This is given for patients with high oxalate levels.

• Magnesium oxide — Given to help lower oxalate acid levels in the urine.

• Tamsulosin (Flomax^®) — Relaxes muscles in the ureter to improve the chance a stone will pass on its own.

• Allopurinol — Lowers the level of uric acid in the blood and in the urine; however, this is rarely necessary.