The main manifestations of drug dependence include the following: 1. psychological dependence, patients mainly show psychological cravings, and if they do not use drugs, they will become anxious and irritable; 2. somatic dependence, if patients do not use drugs, their bodies will experience various discomforts, such as vomiting, profuse sweating, rapid heartbeat and other symptoms; 3. tolerance to drugs, patients often use drugs for the first time When patients use drugs for the first time, they may use a relatively small dose to obtain psychological as well as physical satisfaction, and as time lengthens, the dose becomes larger and larger, and the frequency of use becomes higher and higher, and patients use large doses of drugs to meet their psychological needs.