Bladder stones are hard lumps of minerals that form in the bladder. They're made when the minerals in urine form crystals. This often happens when the bladder does not empty all the way.
Small bladder stones might pass without treatment. But some bladder stones need medicines or surgery. Left untreated, bladder stones can lead to infections and other problems.
Sometimes bladder stones cause no problems. But if a stone irritates the bladder wall or blocks the flow of urine, symptoms might include:
Bladder stones can develop when the bladder doesn't empty all the way. When this happens, there are more minerals than fluid in the urine, making it concentrated. Concentrated urine can turn into crystals that form stones.
Some infections can lead to bladder stones. Sometimes a condition that affects the bladder's ability to hold or get rid of urine can result in bladder stones. Anything in the bladder that shouldn't be there, called a foreign object, also can cause a bladder stone to grow on top of it.
Most often, the following conditions cause bladder stones:
Other possible causes of bladder stones include:

The urinary system includes the kidneys, ureters, bladder and urethra. The urinary system removes waste from the body through urine. The kidneys sit toward the back of the upper abdomen. They filter waste and fluid from the blood and make urine. Urine moves from the kidneys to the bladder through narrow tubes called the ureters. The bladder stores urine until it's time to urinate. Urine leaves the body through a small tube called the urethra.

Your urinary system includes the kidneys, ureters, bladder and urethra. The urinary system removes waste from the body through urine. The kidneys are located toward the back of the upper abdomen. They filter waste and fluid from the blood and produce urine. Urine moves from the kidneys through narrow tubes to the bladder. These tubes are called the ureters. The bladder stores urine until it's time to urinate. Urine leaves the body through another small tube called the urethra.
Men, especially those over 50, are more likely to have bladder stones. But women and children also can get them.
Conditions that can raise the risk of bladder stones include:
Bladder stones that don't pass, even if they don't cause symptoms, can lead to problems, such as:
You may not be able to prevent a condition that causes bladder stones. But you may be able to lower the chances of getting bladder stones. Follow these tips: