Kidney Stones Prevention

If you've had more than one kidney stone, you are likely to form another; so prevention is very important. In most cases, kidney stones can be avoided by making a few lifestyle changes. In some cases, the doctor may prescribe certain medications.

Lifestyle Changes

A simple and most important lifestyle change to prevent stones is to drink more liquids—water is best. If you tend to form stones, you should try to drink enough liquids throughout the day to produce at least 2 quarts of urine in every 24-hour period.

People who form calcium stones used to be told to avoid dairy products and other foods with high calcium content. But recent studies have shown that foods high in calcium, including dairy products, may help prevent calcium stones. Taking calcium in pill form, however, may increase the risk of developing stones.

You may be told to avoid food with added vitamin D and certain types of antacids that have a calcium base. If you have very acidic urine, you may need to eat less meat, fish, and poultry. These foods increase the amount of acid in the urine.

To prevent cystine stones, you should drink enough water each day to dilute the concentration of cystine that escapes into the urine, which may be difficult. More than a gallon of water may be needed every 24 hours, and a third of that must be drunk during the night.

Foods and Drinks Containing Oxalate

People prone to forming calcium oxalate stones may be asked by their doctor to cut back on certain foods if their urine contains an excess of oxalate:

beets
chocolate
coffee
cola
nuts
rhubarb
spinach
strawberries
tea
wheat bran

People should not give up or avoid eating these foods without talking to their doctor first. In most cases, these foods can be eaten in limited amounts.

Medical Therapy

The doctor may prescribe certain medications to prevent calcium and uric acid stones. These drugs control the amount of acid or alkali in the urine, key factors in crystal formation. The drug allopurinol may also be useful in some cases of hyperuricosuria.

Doctors usually try to control hypercalciuria, and thus prevent calcium stones, by prescribing certain diuretics, such as hydrochlorothiazide. These drugs decrease the amount of calcium released by the kidneys into the urine by favoring calcium retention in bone. They work best when sodium intake is low.

Very rarely, patients with hypercalciuria may be given the drug sodium cellulose phosphate, which binds calcium in the intestines and prevents it from leaking into the urine.

If cystine stones cannot be controlled by drinking more fluids, your doctor may prescribe drugs such as Thiola and Cuprimine, which help reduce the amount of cystine in the urine.

For struvite stones that have been totally removed, the first line of prevention is to keep the urine free of bacteria that can cause infection. Your urine will be tested regularly to be sure that no bacteria are present.

If struvite stones cannot be removed, your doctor may prescribe a drug called acetohydroxamic acid (AHA). AHA is used with long-term antibiotic drugs to prevent the infection that leads to stone growth.

Reference:

National Kidney and Urologic Diseases Information Clearinghouse, USA.