Drugs used to treat hepatic encephalopathy include drugs to clean the intestinal tract, antibiotics, probiotic preparations, drugs to promote ammonia metabolism in the body, and branched-chain amino acids. Protein metabolism in the digestive tract produces ammonia, ammonia is diffused into the blood through the intestinal mucosa, blood ammonia is elevated after poor liver function and portal shunt surgery, and ammonia in the blood can cross the blood-brain barrier and interfere with brain function. Therefore, attention should be paid to control blood ammonia in the treatment of hepatic encephalopathy. Lactulose, lactitol, etc. can clean the intestinal tract and reduce the generation and absorption of nitrogen-derived toxic substances in the intestines; antibiotics can inhibit urease-producing bacteria in the intestines and reduce the generation of ammonia, and the commonly used antibiotics are Rifaximin, Metronidazole, Neomycin, etc. L-Ornithine-L-Menthionine can reduce blood ammonia and reduce cerebral edema; Branched-chain amino acid is a kind of compound amino acid with leucine, isoleucine, valine and so on as the main amino acid, its mechanism is to reduce the formation of pseudo-neurotransmitter, but the efficacy is still controversial. In addition, the treatment of patients with hepatic encephalopathy should pay attention to the removal of causative factors, active treatment of primary diseases and protection of liver function. If hepatic encephalopathy is diagnosed, early and standardized treatment is recommended to minimize the adverse effects of the disease. The use of medication should be in accordance with the doctor’s prescription.