According to the medical history and examination results, through medical history inquiry or interview, physical examination, experimental diagnosis and imaging examination, the less likely diagnosis is excluded from many differential diagnoses, and the most likely diagnosis is obtained; After the diagnosis, drug treatment methods include follow-up, lifestyle, drugs and interventional therapy (such as cardiac catheterization and endoscopy). And adjust the use of drugs according to the patient's condition to prevent and deal with side effects and complications.

Internal medicine includes sub-specialties classified according to different organ systems: cardiology, respiratory medicine, hepatobiliary gastroenterology and nephrology (urology)

Gastroenterology division

Hematology, Oncology, Endocrinology, Infectious Diseases, Immunology, Rheumatology, Neurology, Pediatrics, Neurology, Geriatrics, etc. However, the classification of sub-specialties in different places and even hospitals may be different. Most sub-specialties have set up their own medical associations to review the qualifications of sub-specialties and hold academic activities. In a broad sense, internal medicine also includes non-surgical specialties such as dermatology, ophthalmology, psychiatry, rehabilitation (rehabilitation), radiology, palliative care, environment and occupational diseases.

Surgery is a science that studies the occurrence, development, clinical manifestations, diagnosis, prevention and treatment of surgical diseases, and it is a professional department with surgical resection and repair as the main treatment means. With the application of microsurgery technology, great progress has been made in surgery. The principles of specialty setting of surgery in hospitals are similar to those of internal medicine, and usually correspond to internal medicine. Surgical diseases are divided into five categories: trauma, infection, tumor, deformity and dysfunction. The branch of medicine that treats internal and external diseases by surgery. Not internal medicine.

Surgery is mainly divided into general surgery, cardiothoracic surgery, urology, orthopedics, neurosurgery, burns, plastic surgery, microsurgery and so on.