Kidney stones are hard deposits that form in your kidneys. They’re made up of waste products that generally pass through your urine. A kidney stone can be tiny, like a grain of sand, or bigger than a pea. They occur when too much of a particular substance (such as calcium) is in your urine.
Kidney stones develop over time. The deposits may stay in the kidney or travel down the urinary tract. If the stone is too large to pass on its own, it can get trapped along the way and cause blockage, pain, or infection. On the other hand, small stones may pass without causing symptoms.
Types of Kidney Stones
There are four main types of kidney stones:
Calcium stones: These are the most common type of kidney stones. They develop when there’s too much calcium in your urine. Calcium is a mineral in many foods and drinks, including milk, cheese, yogurt, and leafy green vegetables.
Struvite stones: These occur after an infection, such as a urine infection. Struvite stones are relatively rare but can increase and become quite large if left untreated.
Uric acid stones: Uric acid is another waste product that usually leaves your body through your urine. But if too much uric acid is in your urine, it can form crystals in urine. Uric acid stones can develop if you have gout or certain blood disorders. They’re also more common in people who eat a lot of protein or are obese.
Cystine stones develop when you have an inherited disorder that causes an amino acid called cystine to leak from your kidneys into your urine. Cystine stones are relatively rare but can occur at any age and tend to run in families.
The best way to prevent kidney stones is to drink plenty of fluids—six to eight glasses per day—and to avoid foods that contain high levels of oxalate, such as spinach and nuts. Cutting back on salt can also help prevent kidney stones from forming.
If you develop kidney stones, several treatment options are available depending on the size and location of the stone(s). Treatment options include drinking lots of fluids, taking pain medication, using sound waves to break up the stone(s), or having surgery to remove them.
Kidney stones can be painful, but they’re usually not serious, and most people make a full recovery within one to two weeks. However, if you have an infection or obstruction caused by kidney stones, you may need treatment with antibiotics or surgery to clear the blockage. In rare cases, kidney stones can permanently damage the kidneys or urinary tract, so you must seek medical attention immediately if you think you may have them!