Octreotide is an artificially synthesized octapeptide cyclic compound of natural somatostatin. As a homologue of natural somatostatin, it is not easily destroyed by enzymes, has a long half-life, and maintains the pharmacological activity of natural somatostatin with a long-lasting effect. Octreotide can selectively inhibit the secretion of multiple hormones such as growth hormone, glucagon, insulin, and at the same time inhibit the secretion of thyrotropin, adrenocorticotropic hormone, etc. In addition, it can also inhibit the secretion of gastric acid and pancreatic amylase, slow down the transit time of the gastrointestinal tract, promote the absorption of water and electrolytes, constrict visceral blood vessels, and reduce portal pressure and blood flow.