Norepinephrine generally refers to norepinephrine, which can be used to treat gastrointestinal bleeding. The principle is that norepinephrine can constrict the mucosal blood vessels and reduce blood flow, thus playing a role in stopping bleeding. In the treatment of upper gastrointestinal bleeding, norepinephrine is usually prepared as a solution of norepinephrine, which is added to an appropriate amount of chilled saline and chilled mineral water and administered orally or through a gastrointestinal decompression tube into the stomach cavity. If a gastrointestinal decompression tube has been used, the accumulated blood in the gastric cavity should be suctioned sufficiently before administering the drug, so that the norepinephrine solution can be in full contact with the surface of the gastric mucosa, thus exerting the effect of vasoconstriction and achieving the purpose of hemostasis. In addition, if a bleeding lesion is found during gastroscopy, the above-mentioned norepinephrine solution can be sprayed directly onto the surface of the lesion through the biopsy clamp tract of the endoscope with a clear field of view exposure, which can exert a very good hemostatic effect. If the patient’s blood pressure drops, blood volume should be actively maintained with treatment of fluid replacement and pressure elevation. If the amount of gastrointestinal bleeding is large, endoscopic hemostasis can also be performed under endoscopy, and surgical hemostasis treatment can be performed if necessary.