Once diagnosed with depression clinically, it is necessary to optimize and grade the treatment based on the severity of the patient's condition. Particularly for patients with moderate to severe depression, clinical doctors primarily consider pharmacotherapy, especially drugs that improve neurochemicals like serotonin and norepinephrine in the brain. The first-line medications recommended are serotonin reuptake inhibitors. In addition, during the medication process, it is important to ensure adequate dosage, full treatment duration, and systematic standardized treatment throughout the course of the disease. Additionally, in terms of psychological and physical therapies, cognitive-behavioral therapy is predominant in psychological treatment. It includes helping patients identify emotions, thoughts, behaviors, and effectively reconstructing systems to achieve therapeutic goals. For physical therapy options, repeated transcranial magnetic stimulation, light therapy, and electroconvulsive therapy can be considered. (Please follow professional medical advice for medication usage.)