This duct then joins with a duct coming from the gallbladder, called the cystic duct, to form the common bile duct. The pancreatic duct joins the common bile duct just where it empties into the duodenum. Between meals, bile salts are concentrated in the gallbladder, and only a little bile flows from the liver. Food that enters the duodenum triggers a series of hormonal and nerve signals that cause the gallbladder to contract. As a result, bile flows into the duodenum and mixes with food contents.
Bile salts stimulate the secretion of water by the large intestine to help move the contents along.
Drugs and other waste products are excreted in bile and later eliminated from the body. Various proteins that play important roles in bile function are secreted in bile. Bile salts are reabsorbed into the small intestine, extracted by the liver, and resecreted into bile. This recirculation of bile salts is known as the enterohepatic circulation. All the bile salts in the body circulate about 10 to 12 times a day.