Causes of hiccups: 1. hiccups are caused by diaphragm spasm and eating too fast. 2. hiccups are caused by certain diseases, especially diseases of the brain, such as brain tumors, cerebrovascular accidents, encephalitis, meningitis, because of damage to the reflex nerve that causes erratic reflexes. 3. some reflex arcs are stimulated. The hiccups are caused by stimulation of the phrenic nerve, such as mediastinal tumor, esophagitis, esophageal cancer, pneumonia, pleurisy, pericarditis, gastritis, gastric cancer, etc. 4.