Tags: Disease.
Post-nasal drip (PND also termed upper airway cough syndrome UACS or post nasal drip syndrome PNDS) occurs when excessive mucus is produced by the nasal mucosa. The excess mucus accumulates in the throat or back of the nose. It is caused by rhinitis sinusitis gastroesophageal reflux disease (GORD) or by a disorder of swallowing (such as an esophageal motility disorder).