Digestive drugs (digestants) aid digestion in the patient who’smissing enzymes or other substances needed to digest food. Di-gestants that function in the GI tract, liver, and pancreas include:
· amylase (pancreatic enzymes).
Digestants aren’t absorbed; they act locally in the GI tract and are excreted in stool.
The action of digestants resembles the action of the body sub-stances they replace. Pancreatic enzymes replace normal pancre-atic enzymes. They exert their effect in the duodenum and upper jejunum of the upper GI tract.
These drugs contain trypsin to digest proteins, amylase to digest carbohydrates, and lipase to digest fats.
Because their action resembles the action of the body substances they replace, each digestant has its own indication.
Pancreatic enzymes are administered to the patient with insuffi-cient levels of pancreatic enzymes, such as the patient with pan-creatitis or cystic fibrosis. They may also be used to treat steator-rhea (disorder of fat metabolism characterized by fatty, foul-smelling stool).
Antacids reduce the effects of pancreatic enzymes and shouldn’t be given at the same time. Pancreatic enzymes may decrease the absorption of folic acid and iron. (See Adverse reactions to diges-tive drugs.)