The rational and safe use of drugs is closely related to everyone’s health, however, the irrational use of drugs is very common in China, seriously endangering people’s health. Water can carry the boat, but also can overturn the boat, medicine can bring health, but also can harm health. The incidence of various diseases caused by unreasonable use of drugs is increasing year by year, some information shows that in China every year due to adverse drug reactions caused by the death of about 190,000 people, the average daily death of about 520 people, the unreasonable use of drugs is one of the important reasons. Irrational use of drugs is mainly manifested by ignoring the side effects of drugs, repeated use of drugs, advertising drugs, purchase of drugs in informal medical institutions, improper compounding, use of expired drugs, inaccurate dose, improper method of taking drugs, drug abuse, etc.. Irrational use of drugs not only causes economic losses, but more importantly, delays the disease, damages the patient’s health, and even threatens the life. The liver has a close relationship with drugs and is the main metabolic organ of drugs, as well as the main target organ for the occurrence of pharmacogenic diseases. In recent years, the incidence of pharmacogenic liver disease, which is a category of pharmacogenic diseases, has been increasing. The use of drugs that are toxic to the liver, the arbitrary increase of drug doses due to poor control of the disease, the arbitrary use of drugs ignoring the contents of the instructions (contraindications, adverse reactions, precautions, etc.), the ignoring of drug interactions and the use of drugs with contraindications, the ignoring of the appropriate dosage for special groups (elderly, children, pregnant women and alcoholics, etc.), the long-term use of herbal medicines, the use of expired drugs, drug abuse and other irrational The use of drugs is one of the most important reasons for the increased incidence of drug-related liver disease. Currently, it is known that drugs that may cause drug-induced liver disease include antibiotics, antipyretic and analgesic agents, antituberculosis drugs, antitumor drugs, drugs for the treatment of neurological diseases, drugs for the treatment of digestive diseases, narcotics, drugs for the treatment of metabolic diseases, hormonal drugs, etc. Drug-induced liver damage depends on two factors: one is the direct or indirect damage to the liver by the drug itself, which is often predictable; the other is the idiosyncratic response of the organism to the drug, which is mostly unpredictable. The liver damage caused by drug-induced liver disease includes hepatocellular damage, bile depression or both, and is mostly accompanied by other diseases. The biliary depression type is characterized by fever, rash, itchy skin, jaundice, right upper abdominal pain, significantly elevated serum conjugated bilirubin, and moderate elevation of alkaline phosphatase with transaminases. The clinical manifestations of the mixed form have both of these features. The liver damage caused by drug-related liver disease can be acute, subacute and chronic, ranging in severity from asymptomatic and mild to decompensated and life-threatening liver function. Therefore, the rational use of drugs to reduce the occurrence of drug-induced diseases and damage to the liver should be given sufficient attention. The most basic requirement of rational drug use is to administer the appropriate drug, in the appropriate dose, to the appropriate patient at the appropriate time and by the appropriate route of administration, and to obtain the maximum expected therapeutic effect with the minimum therapeutic risk. The rational use of drugs should be carried out under the guidance of an experienced physician or clinical pharmacist, who should strictly grasp the indications and read the instructions carefully, avoid using multiple drugs at the same time, stop using or avoid using hepatotoxic drugs as far as possible, choose the appropriate dose and method of administration, reasonably combine drugs to reduce the safety risks or reduce the efficacy caused by drug interactions, pay attention to the safety of combined drugs, pay attention to the observation of drug reactions and We should pay attention to the safety of combined medication, observe the reaction of medication and adjust the medication in time, and make a reasonable treatment plan for special populations by carefully selecting medication. To protect the liver, we should start with the rational use of drugs.