Paroxysmal nocturnal dyspnoea or
paroxysmal nocturnal dyspnea (
PND) refers to attacks of severe
shortness of breath and coughing that generally occur at night. It usually awakens the person from sleep, and may be quite frightening. Though simple
orthopnea may be relieved by sitting upright at the side of the bed with legs dangling, in those with PND, coughing and wheezing often persist in this position.