Retention of phlegm heat in the lung

Clinical manifestations : Cough, asthmatic and coarse breathing ; flapping of ala nasi in severe cases ; yellow, thick sputum or expectoration of foul smelling bloody pus ; chest pain on coughing, dryness of the mouth, yellow urine, constipation, a red tongue with yellow, sticky coating and a rolling, rapid pulse.

Etiology and pathology : This syndrome is often due to invasion of exogenous pathogenic wind heat, or invasion of wind cold which goes to the interior of the body and turns into heat after a period of retention. Heat in the lung changes body fluid into phlegm by condensation. The phlegm and heat intermingle and impair the descending function of the lung, the result being cough, asthmatic breathing, chest pain and yellow, thick sputum. Phlegm heat blocks the vessels of the lung, which leads to decomposition and thereby produces pus, effecting expectoration of bloody pus. Consumption of body fluid by pathogenic heat gives rise to dryness of the mouth and yellow urine. Failure of the lung qi in descending is the cause of constipation. A yellow, sticky tongue coating, a red tongue and a rolling, rapid pulse are all signs of retention of phlegm heat in the interior.