Your gallbladder is a pear-shaped organ under your liver. It stores bile, a fluid made by your liver to digest fat. As your stomach and intestines digest food, your gallbladder releases bile through a tube called the common bile duct. The duct connects your gallbladder and liver to your small intestine.
Your gallbladder is most likely to give you trouble if something blocks the flow of bile through the bile ducts. That is usually a gallstone. Gallstones form when substances in bile harden. Gallstone attacks usually happen after you eat. Signs of a gallstone attack may include nausea, vomiting, or pain in the abdomen, back, or just under the right arm.
Gallstones are most common among older adults, women, overweight people, Native Americans and Mexican Americans.
Gallstones are often found during imaging tests for other health conditions. If you do not have symptoms, you usually do not need treatment. The most common treatment is removal of the gallbladder. Fortunately, you can live without a gallbladder. Bile has other ways to reach your small intestine.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases
