According to experts, teenagers' physical and mental development is not yet mature. Once addicted to drugs, it will lead to memory loss, severe malnutrition, decreased resistance and many diseases. 2) It has serious damage to human immune function. 3) Harm of withdrawal reaction to human body: Many people will have severe withdrawal reaction and various complications, which often lead to death, and even commit suicide due to unbearable pain when stopping drug or reducing dosage suddenly. Direct toxicity to human body: long-term drug abuse is harmful to human body mainly in the central nervous system, accompanied by dysfunction and histopathological changes of other organs. At this time, the main symptoms of people are listlessness, insensitivity, and the harm that modern drugs bring to individuals. The first thing to bear is the luxury of money. No matter how rich a family is, most of them will only end up in a helpless family in the face of drugs. Once a person is addicted to drugs, he will lose his sense of obligation or responsibility. The husband can't fulfill his husband's responsibility, and the wife can't fulfill her wife's responsibility, which will inevitably lead to the brink of family breakdown. Dyskinesia, hallucinations, delusions, disorientation and sexual dysfunction.