Inclusion Criteria:  aged 18 to 55 Those who can understand and obey the research plan Sign the informed consent form voluntarily Those who meet the DSM-IV-TR depression diagnostic criteria and have first or second episodes of depression Hamilton Depression Scale score ≥ 14 points Those who meet the ICD-11 pain diagnostic criteria, and visual analogue scale score ≥ 7 points. Those who have chronic visceral pain instead of cancer pain.  No systemic use of antidepressants and analgesics within 2 weeks after enrollment.  -  Exclusion Criteria:  Female patients who are pregnant, breastfeeding, or preparing to conceive Allergic to duloxetine or pregabalin in the past. A history of serious or unstable physical diseases, such as cardiovascular/liver/kidney/respiratory/ endocrine/nervous/ blood system disease. A history of epileptic seizures or brain injury, or any neurological disease (including multiple sclerosis, degenerative diseases such as acute lateral sclerosis, Parkinson's disease and movement disorders, etc.); In the last 12 months, the patient has the following medical history or its main diagnosis (DSM-IV-TR) is organic mental disorder, schizophrenia, schizoaffective mental disorder, delusional mental disorder, indeterminate mental disorder, Bipolar disorder, psychotic characteristics that are coordinated or uncoordinated with the mood, and history of substance abuse (including alcohol, psychoactive substances, etc.). Patients with a history of adverse reactions to multiple drugs. The patient is taking psychotropic drugs, including benzodiazepines, sleeping pills, anticonvulsants, etc. During the depressive episode, treatment with at least 2 antidepressants in a sufficient course of treatment or at least one SSRI antidepressant treatment is ineffective. A sufficient dose of treatment means treatment with fluoxetine ≥40 mg/day (or sertraline ≥100 mg/day, paroxetine> 40 mg/day, fluvoxamine> 100 mg/day, citalopram> 40 mg /Day, escitalopram> 20 mg/day, venlafaxine> 150 mg/day, duloxetine> 80 mg/day) Received electroconvulsive therapy within 6 months before enrollment.  Those who are currently at serious risk of suicide, and a score of 3 or higher in item 3 of the 17-HAMD .  -