Antidepressants are a large group of many psychotropic drugs, mainly used to treat depression and various depressive states. Although there are more antidepressants available, certain principles need to be followed to choose the right drug for practical application, mainly the following: 1. Use a single drug as much as possible. At least at the beginning of treatment, in order to observe the effect and prevent adverse side effects, it is not appropriate to combine a variety of antidepressants. For refractory cases or with psychotic symptoms, it is a different story. 2. The principle of initial medication is that the dose should be increased from small doses and sufficient therapeutic doses should be achieved. New generation antidepressants have less side effects and can be applied immediately in sufficient doses. 3.Safety radicals are well tolerated. 4, adverse reactions are light, and easy to take, which can enhance the patient’s tolerance and compliance with the drug. 5.Explain to the patient that the drug must be taken daily, and that improvement will not occur until 2-3 weeks after the start of treatment, and that minor side effects may occur but usually disappear after 7-10 days. It should be emphasized that patients should seek medical advice before discontinuing the medication. Antidepressant treatment should be continued for at least three months after the situation improves. 6.For patients with suicidal ideation avoid prescribing a large number of drugs at one time to prevent accidents, and less dangerous drugs can be used. 7.If the patient is satisfied with the efficacy of a drug in the past, the drug can be chosen again. 8, if the patient is older or has physical disorders, you can use less anticholinergic and cardiovascular side effects of the drug. 9, if the patient is accompanied by anxiety or sleep difficulties, you can use drugs with strong sedative effects. 10.If the patient is predominantly psychomotor depressed, drugs with less sedative effect can be chosen. 11.When accompanied by psychotic symptoms, it can be used in combination with psychiatric drugs or combined with electroconvulsive therapy at the same time. 12.The price is reasonable.