Kidney stones are just what they sound like: small stones that form inside the kidneys. They form when salts and minerals that are normally in the urine build up and harden.

Kidney stones usually get carried out of the body when you urinate. But sometimes they can get stuck on the way out. If that happens, the stones can cause:

• Pain in your side or in the lower part of your belly
• Blood in the urine (which can make urine pink or red)
• Nausea or vomiting
• Pain when you urinate
• The need to urinate in a hurry

If your doctor or nurse thinks you have kidney stones, he or she can order an imaging test that can show the stones.