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What are kidney stones?

This common problem can often be treated at home.

Kidney stones are one of the most common problems affecting the urinary system. The Urology Care Foundation (UCF) reports that about 13% of American men and 6% of women will will have a kidney stone at least once in their lives. 

The symptoms of kidney stones include:

• Severe pain, usually in the lower back, side or groin.
• Nausea and vomiting.
• Frequent and painful urination.
• Weakness, fever and chills.
• Blood in the urine.
• Blocked urination.

How stones form

Kidney stones form when crystals separate from the urine and stick to the inner surfaces of the kidney. They range in size from a grain of sand to a golf ball.

Several factors affect your kidney stone risk:

• A family history of kidney stones.
• Kidney disorders.
• Metabolic disorders (problems that interfere with how your body digests or uses food).
• Chronic urinary tract infections.
• Limited activity for several weeks.
• Misuse of some medications.

Most kidney stones are made of calcium combined with other substances. Others consist of uric acid or cystine.

Passing stones

Most kidney stones will pass out of the urinary tract on their own or with a little help.

People waiting for stones to pass should continue to drink normal amounts of water, according to the UCF, enough to make at least 2.5 liters of urine per day. Many stones can be passed at home with the help of pain relievers.

Other treatments include medication, the use of sound shock waves to break up the stones, and surgical removal.

Preventing stones

According to the National Institutes of Health, the easiest and best way to prevent kidney stones is to drink plenty of liquids, preferably water. Dietary changes are helpful in some cases, as well as medication.

Reviewed 2/22/2024