Hiccups are caused by involuntary spasms or contractions of the diaphragm, the dome-shaped muscle beneath the lungs that plays a key role in breathing. When the diaphragm spasms, it suddenly pulls air into the throat, causing the vocal cords to snap shut and produce the characteristic "hic" sound. Common triggers for hiccups include eating or drinking too much or too quickly, drinking carbonated beverages or alcohol, emotional excitement or stress, sudden temperature changes, and swallowing air. These triggers irritate the diaphragm or the nerves that control it, such as the vagus and phrenic nerves. In most cases, hiccups are harmless and resolve quickly on their own. However, persistent hiccups lasting more than 48 hours may indicate underlying medical conditions affecting the nerves, diaphragm, or central nervous system and require medical attention.
