Chronic Cough — When the Cough Lingers After a Cold

The cold is gone, but the cough remains

When a cough persists for 3 to 8 weeks after a viral cold has cleared, it is called post-infectious cough. The virus damages the bronchial mucosa, leaving the cough reflex hypersensitive — this is different from a bacterial infection that would require antibiotics.

Korean medicine diagnosis: Lung yin deficiency (肺陰虛)

While fighting the cold, the body's lung fluids (yin) become depleted, leaving the lungs in a dry state.

• Dry cough: A hacking cough without phlegm — the dry lung mucosa is hypersensitive to stimuli
• Sticky, scant phlegm: Insufficient fluids leave the phlegm thickened and hard to expectorate
• Worse at night: Parasympathetic activation tightens the bronchi, compounded by dry indoor air

Treatment

• Maekmundong-tang (麥門冬湯, Mai Men Dong Tang): The signature formula for replenishing lung fluids — Ophiopogon, Pinellia, Ginseng, Licorice, glutinous rice, jujube
• Baekhap-gogeum-tang (百合固金湯): For severe lung yin deficiency, especially when sputum is blood-tinged
• Acupuncture: Feishu (BL13), Chize (LU5), and Lieque (LU7) — restore lung function and suppress the cough

If the cough lasts more than 8 weeks

Other causes such as cough-variant asthma, laryngopharyngeal reflux, or upper airway cough syndrome (postnasal drip) need to be ruled out. We recommend a chest X-ray or pulmonary function test at that point.