Gallstones are rocklike substances that form inside the gallbladder, a sac-shaped organ that is on your right side, just under the liver. About 80 percent of gallstones are made of cholesterol, with the remaining 20 percent made of bilirubin, or a combination of bilirubin, cholesterol, and other substances.
Gallstones can be small or as large as a golf ball. They occur more commonly in women, in older people, overweight people who lose weight suddenly, American Indians, and people with diabetes. They also occur more frequently in women who have been exposed to higher amounts of estrogen during their lifetime through birth-control pills or hormone therapy. Estrogen causes the liver to remove cholesterol from the blood. Pregnancy also increases the risk.
The gallbladder stores bile, which is made in the liver and used to help digest fats in food. The bile is a mixture of water, cholesterol, fats, proteins, bile salts, and wastes, including bilirubin.
Gallstones usually don't cause any symptoms or problems. Small ones typically leave the gallbladder and pass out of the body through the intestines. The stones can cause symptoms, however, if they get caught in the gallbladder's narrow outlet.
After meals, especially high-fat ones, a muscle in the gallbladder wall squeezes to help empty bile into the intestines. If this muscle squeezes against a gallstone, or if a stone blocks the draining fluid, the muscle and the gallbladder can become painful.
More serious problems can develop if a stone gets into the drainage duct system but doesn't move to the intestines. A buildup of bile can cause infection in the gallbladder, liver, or pancreas.
Learn the symptoms
Eighty percent of people with gallstones have no symptoms and don't require treatment. When gallstones do cause symptoms, this is what you might experience:
Severe or persistent pain in the right side of the abdomen, mid-abdomen, or back; the pain can last from 15 minutes to several hours each time it occurs
Jaundice. A yellowing of the skin or eyes.
An unexplained fever
Intolerance to fatty foods
Belching, gas, nausea, or a general decrease in appetite
Diagnosis and treatment options
Most gallstones don't show up on regular X-rays, but they are usually seen easily with an ultrasound test.
Most people whose gallstones cause symptoms need treatment. Nearly 90 percent of patients who seek treatment undergo a type of surgery called laparoscopic cholecystectomy. In this procedure, a surgeon uses a small light and camera placed through a small incision in the abdomen. Using instruments placed through other small incisions, the surgeon deflates the gallbladder by removing fluid and stones, then removes the gallbladder.
Work on prevention
Gallstones are less likely to form if you control your weight. If you're overweight, avoid quick weight-loss diets. Reduce your intake of saturated fats. Certain medicines, such as birth-control pills and estrogen, can increase the likelihood of gallstones. Talk to your health care provider if you have questions about the medications you take.