A hiccup is a repeated involuntary spasmodic contraction of the diaphragm followed by a sudden closure of the glottis which checks the inflow of air and produces the characteristic sounds. Hiccups result when afferent or efferent nerves to the muscles of respiration, or the medullary centres controlling these muscles are irritated. The underlying pathophysiology of intractable hiccups remains to be elucidated but is believed to involve organic, drug-induced, and/or psychological causes.
Classification of Hiccups
Hiccups are classified according to their duration:
- Acute hiccups are defined as hiccups that last up to 48 hours.
- Persistent hiccups are hiccups that last for over 48 hours.
- Intractable hiccups are defined as hiccups that last more than one month or two months. Intractable hiccups may result in severe discomfort, decreased physical strength and mental depression if left untreated.