Past medical history refers to the history of illnesses suffered prior to this visit. It is important to focus on asking about the history of each major organ, such as the heart, liver, spleen, lungs, and kidneys, as well as the history of psychiatric and psychological disorders. In the medical history, the past medical history includes past health, prophylactic injections, surgical procedures or hospitalizations, adverse events that have occurred and their impact on health, and food and drug allergies. When answering the past medical history, the patient should carefully recall any history of related surgeries and the prognosis. The more detailed the past medical history, the more it will help the doctor to make the right diagnosis and treatment, which is very helpful for the recovery of the disease.