What are hiccups? Hiccups are sudden, involuntary contractions of the diaphragm muscle. As the muscle contracts repeatedly, the opening between the vocal cords snaps shut to check the inflow of air and makes the hiccup sound. Irritation of the nerves that extend from the neck to the chest can cause hiccups. Common Causes of Hiccups … Continue reading 12 Home Remedies to Stop Hiccups Instantly