The gall bladder is a small sac located just under the liver. It stores bile, a digestive fluid produced by the liver that helps digest fats. Gallstones form from cholesterol and other bile components. When high amounts of fat are present, crystals form and combine to form stones. They can range in size from a small grain of sand to a large golf ball.

Most gallstones don’t cause problems or symptoms and thus don’t need treatment. But if a person experiences pain in the right upper abdominal region that lasts longer than one to two hours or is associated with a fever, he or she should see a doctor. Symptomatic gallstones are usually removed during surgery.