There is no such thing as an antidepressant with fewer side effects because everyone has different sensitivities and responses to medications. Clinical first-line antidepressants mainly include selective 5-hydroxytryptamine reuptake inhibitors, 5-hydroxytryptamine and norepinephrine reuptake inhibitors, norepinephrine and specific 5-hydroxytryptaminergic antidepressants. 1. Selective 5-hydroxytryptamine reuptake inhibitors: they are commonly prescribed for the treatment of depression and may cause adverse reactions such as nausea, vomiting, diarrhea or constipation. However, the symptoms are mild and short-lived, representing drugs such as fluoxetine and paroxetine. 2. 5-hydroxytryptamine and norepinephrine reuptake inhibitors: representative drugs are duloxetine, venlafaxine, etc., which have good efficacy for various kinds of depression, and there will be gastrointestinal adverse reactions in the initial stage of treatment, but they will be gradually reduced. 3. Norepinephrine and specific 5-hydroxytryptamine antidepressants: representative drugs include mirtazapine, which is suitable for all kinds of depression and is a dual reuptake inhibitor. Adverse effects such as increased appetite, weight gain and drowsiness may occur. It is recommended that patients with depression use medication under the guidance of a doctor, do not use it without authorization to avoid adverse reactions.