The pancreas is an organ located behind the stomach that produces chemicals called enzymes, as well as the hormones insulin and glucagon. Most of the time, the enzymes are only active after they reach the small intestine, where they are needed to digest food. When these enzymes somehow become active inside the pancreas, they eat (and digest) the tissue of the pancreas. This causes swelling, bleeding (hemorrhage), and damage to the pancreas and its blood vessels. Acute pancreatitis affects men more often than women. Certain diseases, surgeries, and habits make you more likely to develop this condition.