Hiccups but not acid reflux may be related to reflux esophagitis, diaphragmatic spasm, mental and other reasons. 1. Reflux esophagitis: hiccups but not acid reflux may be the body suffers from reflux esophagitis, affected by the disease often hiccups, in addition to heartburn, bloating and other discomforts. 2. Diaphragmatic spasm: hiccups but not acid reflux may be caused by diaphragmatic spasm, eating too fast, too much or eating complex and indigestible food is easy to diaphragmatic spasm, causing hiccups and other discomforts. 3. Improper diet: hiccups without acid reflux can also be considered with mental factors, long-term stress, depression and other mental states, easily affect the sympathetic nervous system disorders, gastrointestinal function is inhibited hiccups without acid reflux symptoms. Long-term hiccups without acid reflux, consider going to a regular hospital.