Urological Health What Is a Kidney Stone? By Laura Newman Laura Newman is an award-winning journalist with expertise in clinical medicine, health policy, urology, oncology, neurology, and targeted therapies. Learn about our editorial process Laura Newman Medically reviewed by Medically reviewed by Susan Olender, MD on August 05, 2016 Susan Olender, MD, is board-certified in internal medicine. She is an assistant professor at Columbia University College of Physicians and Surgeons in New York City, where she is also on staff in the Division of Infectious Disease. Learn about our Medical Review Board Susan Olender, MD Updated on May 29, 2020 Print Table of Contents View All Symptoms Causes Diagnosis Treatment Prevention Kidney stones are solid, pebble-like masses that develop in the urinary tract from salt and minerals that have clumped together in the urine. The process, called urolithiasis, can result in either a small stone that is easily passed during urination or a larger stone that can block a ureter (one of two tubes which propel urine from the kidney). 1:29 Kidney Stone Symptoms When a blockage occurs, a person can experience often excruciating pain radiating from the back and sides to the pelvis, groin, and genital areas. In addition to this pain, there are several other common symptoms including: Urinary Urgency (the feeling you need to urinate constantly)Intense burning when you try to urinateFever and chillsBlood in your urineNausea and vomitingCloudy urine or urine that smells badLoss of appetiteSweating Restlessness Causes Most kidney stones form as a result of both genetic and environmental factors. Men are more prone to kidney stones than women, as are people between the ages of 30 and 60. Other risk factors include: High urine calcium levelsDehydration or not drinking enough fluidsFamily history of kidney stonesObesityDiets that are high in animal proteinsLow dietary magnesiumHigh sodium intakeDrinking fluoridated waterTaking excessive calcium, vitamin C, or vitamin D supplementsExcessive parathyroid activityGout Verywell / Gary Ferster Kidney stones are also more common in the southern United States, where the persistent, dry heat and dietary factors contribute to their development. As a result, the area is often deemed the "Kidney Stone Belt." There are several types of kidney stones, each of which is linked to various biological, environmental, genetic, and dietary causes. Calcium stones are the most common type. They are seen commonly in post-menopausal women who take excessive calcium and vitamin D supplements (greater than 1000 mg. and 400 IUs, respectively).Uric acid stones occur in people with a high urine acidity (as can happen with gout).Struvite stones tend to develop as a result of infection. Cystine stones are rare and tend to run in families. Diagnosis Imaging tests, including X-ray, ultrasound, and computed tomography (CT scan), can be used to pinpoint the size and exact location of the stone. These tests are extremely helpful in determining whether the stone will pass naturally or require more aggressive treatment. Treatment There are several schools of thought regarding the treatment of kidney stones. Oftentimes, decisions are based on the size and location of the stone. Specialist training and experience will also direct which course of action a urologist will likely take. Conservative treatment is most often indicated in people with smaller stones. The doctor will advise you to drink a lot of water while providing you painkillers to help tolerate the pain. You may also be asked to have a strainer on hand to catch the stone when it passes so that it can be analyzed in the lab. This can help determine which foods or factors led to the stone's formation. For larger stones, a more aggressive approach may be needed, including the following: Extracorporeal shock wave lithotripsy (ESWL) is a technique that uses a specialized machine to break up a stone from outside of your body, allowing you to pass the stone more easily.Percutaneous nephrolithotomy (PCNL) involves inserting a tube through a small incision to help drain the kidney.A ureteroscope is a small, tube-like instrument equipped with a camera, and it can be inserted into the urethra (the opening through which urine is expelled from the body) to either manually extract the stone or break it into tiny pieces. Prevention Whether you've had them in the past or are at risk for developing them, there are plenty of helpful measures you can take to try to prevent kidney stones. Drink more water to continually flush out the urinary tract.Avoid drinking more than one to two cups of caffeinated beverage per day.Restrict your intake of cola or any drink that contains phosphoric acid.Eat less animal protein and refined sugars.Increase your natural intake of citric acid, particularly from lemon or lime juice.Avoid foods containing high fructose corn syrup.Avoid excessive vitamin C supplementation.For oxalate stones, restrict your intake of concentrated citrus juice, chocolate, beer, tea, or dark green vegetables.For calcium stones, restricting your salt intakeFor uric acid stones, reduce your intake of meat, fish, and poultry.Avoid excessive calcium and vitamin D supplementation if you are post-menopausal. Your doctor may also prescribe a diuretic, cellulose phosphate, or potassium citrate to facilitate calcium excretion if you have had calcium stones. A Word From Verywell There are various types of kidney stones that come in different shapes and sizes—they could be a result of various factors including environment, genetics, and diet. If you are experiencing radiating pain in your back, sides, or pelvic region, it is important to seek medical attention immediately. You may have a kidney stone or other undiagnosed condition. If you know you are at risk for developing kidney stones, making healthy changes in your diet could help to prevent your risk of future kidney stones. Prevent Kidney Stones With These Tips Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms & Causes of Kidney Stones. Updated May 2017. National Institute of Diabetes and Digestive and Kidney Diseases. Definition & Facts for Kidney Stones. Updated May 2017. Brikowski TH, Lotan Y, Pearle MS. Climate-related increase in the prevalence of urolithiasis in the United States. Proc Natl Acad Sci U S A. 2008;105(28):9841–9846. doi:10.1073/pnas.0709652105 National Institute of Diabetes and Digestive and Kidney Diseases. Treatment for Kidney Stones. Updated May 2017. National Kidney Foundation. 6 Easy Ways to Prevent Kidney Stones.