The bile travels out of the gallbladder through the cystic duct, a small tube that leads to the common bile duct, and from there into the small intestine. The main cause of cholecystitis is gallstones or biliary sludge getting trapped at the gallbladder's opening. This is sometimes called a pseudolith, or "fake stone." The gallbladder is a small, pear-shaped organ connected to the liver, on the right side of the abdomen. It stores bile and releases it into the small intestine to help in the digestion of fat. The gallbladder holds bile, a fluid that is released after we eat, especially after a meal that is high in fat, and this bile aids digestion. The bile travels out of the gallbladder through the cystic duct, a small tube that leads to the common bile duct, and from there into the small intestine.