The main causes of morning hiccups are: 1. cold at night, because the temperature is cool at night, when sleeping, inhale a lot of cold air, resulting in diaphragm spasm and morning hiccups. 2. heavy alcohol consumption, such as long-term alcohol consumption or heavy alcohol consumption the day before, because the effect of alcohol inhibits the brain’s delayed brain reflex arc, resulting in the disappearance of the brain’s reflex to inhibit hiccups, so the phenomenon of morning hiccups will occur. 3. Stimulation of the vagus nerve, mainly seen in gastritis, pancreatitis, gastric cancer and dilatation of the stomach, stimulates the vagus nerve of the diaphragm in the morning due to the thinning of the body position when waking up, resulting in the phenomenon of morning hiccups. 4. Stimulation of the phrenic nerve, such as esophagitis, esophageal cancer and thoracic aortic aneurysm, also stimulates the phrenic nerve in the morning due to the change of body position, resulting in the phenomenon of morning The phenomenon of hiccups.