Rational drug use refers to the safe, effective, economic, moderate and convenient use of drugs. Safety means using drugs without toxic effects as much as possible to prevent drug-derived diseases caused by improper use of drugs. Effective refers to the selection of the most effective and credible drugs for the treatment of the disease under the premise of clear diagnosis of the patient. Economic means that the selected drug has a high price/performance ratio, which is both economic and practical. Appropriate means that the dosage of the drug is appropriate, the course of treatment is appropriate, and the route is appropriate. Convenience means choosing a simple and quick way of drug administration, minimizing the patient’s burden and pain, and obtaining the best therapeutic effect.