Unrelenting hiccups are also clinically referred to as persistent eruptions. The common causes are: 1. Inhaling a large amount of gas, especially cool gas, when the cool gas stimulates the nerves in the stomach, it can lead to gastric sympathetic excitation, diaphragm spasm and hiccups. 2. Side effects of drugs. When chemotherapy drugs or hormone drugs are applied, they can cause persistent hiccups and even nausea and vomiting because of their side effects. 3. Eating too much. After eating spicy, stimulating, too full, too cold, etc., it can also lead to hiccups. 4, esophageal tumors, subphrenic cysts, pleurisy and other diseases can also lead to diaphragmatic spasm and recalcitrant erratic reflux. 5, reflux diseases. Such as reflux esophagitis and reflux gastritis, reflux can be accompanied by incessant hiccups. 6. mental and psychological factors. Emotional depression can also affect the sympathetic nerves, making them overstimulated and inhibiting gastric motility and emptying function leading to hiccups.