A number of tests are available to see how well the pancreas is making the enzymes that break down food. These include simple stool tests. Sometimes it is important to measure the amount of the enzymes that gets into the small intestine. This is done at the time of an upper endoscopy. After the child is asleep, under anesthesia, they are given a medication through an IV that stimulates the pancreas. This causes fluid from the pancreas to empty out into the first part of the small intestine (duodenum). This fluid is suctioned out through the endoscope and collected in a container. It is then sent to a laboratory where the amount of enzymes in the fluid is measured.