Drinking a warm cup of tea often clears the nasal passages and eases feelings of stuffiness. In line with the Donguibogam view connecting the nose and lungs, modern medicine also treats the nose and lungs as parts of an interactive, integrated system. Postnasal drip refers to a condition where mucus produced in the nasal cavity and paranasal sinuses drains down the back of the throat, causing persistent irritation. This occurs not only from an excess volume of mucus, but also from the interplay of mucus quality, mucosal inflammation, and ciliary dyskinesia.
Modern clinical practice identifies diverse causes for postnasal drip. Inflammatory conditions such as allergic rhinitis and chronic purulent sinusitis are the most frequent. Vasomotor rhinitis, driven by autonomic nervous system dysregulation in the nasal mucosa, also accounts for a significant portion. In addition, esophageal irritation from gastroesophageal reflux disease can provoke or worsen postnasal drip, while thyroid gland dysfunction and certain medication side effects may also be contributing factors.
The Donguibogam insight regarding an SOS signal from the lungs is supported by modern neurology and immunology. The mucous membranes serve as a frontline defense against external pathogenic bacteria and allergens. When chronic inflammation develops in the nasal mucosa, it can compromise the immune function of the entire respiratory tract leading down to the lungs. The autonomic nervous system plays an equally vital role. When the parasympathetic nervous system becomes overactive, mucus secretion rises and blood vessels dilate, aggravating nasal congestion and postnasal drip. These reactions tend to intensify under systemic strain such as stress or sleep deprivation.
Chronic postnasal drip noticeably reduces quality of life. It can lead to a foreign body sensation in throat, chronic cough, and vocal changes, while also causing daytime fatigue, impaired concentration, and low mood due to sleep disruption. Furthermore, mucus running down the back of the throat irritates the larynx and bronchus, which can trigger or aggravate pharyngitis, bronchitis, asthma, and other respiratory disorders. Recognizing postnasal drip as an indicator of broader respiratory well-being rather than a localized annoyance allows for timely and attentive care.
