Left upper abdominal pain is often considered the cause of peptic ulcer, acute pancreatitis, acute cardiopulmonary pleural disease, etc., according to the different causes, under the guidance of the doctor to take acidic gastric drugs, antispasmodic painkillers, dilatation of thrombolytic anticoagulant drugs, etc. for treatment. 1. Peptic ulcer is mainly manifested as recurrent periodic pain in the left upper abdomen, aggravated after eating, and it is often treated with acid-suppressing drugs such as omeprazole as prescribed by the doctor, and gastric drugs such as misoprostol can be added to promote the repair and healing of the ulcer. 2. Abdominal pain in acute pancreatitis is mainly characterized by severe pain in the left upper abdomen with radiating pain in the left shoulder. Often under the guidance of the doctor fasting rehydration at the same time, taking antispasmodic analgesics such as scopolamine, etc., can also be added to the acid suppression drugs such as omeprazole to control symptoms. 3. Acute cardiopulmonary pleural disease: left-sided pneumonia, pleurisy, acute coronary syndrome and other diseases sometimes appear left upper abdominal pain, accompanied by chest tightness, shortness of breath and other typical symptoms of heart attack. The cause needs to be identified before treatment. People with a history of coronary artery disease often choose to expand the coronary artery with nitroglycerin under the guidance of a doctor, and apply such as alteplase within 2 hours, and take anticoagulants such as aspirin 7 to 10 days after thrombolysis. Patients with left upper abdominal pain should seek medical attention in a timely manner, according to the cause of the different treatments under the guidance of the doctor.