Asthma occurs repeatedly due to internal and external causes, and it is divided into stage of attack and remission stage in syndrome differentiation.
At the stage of attack, the disease is often divided into cold asthma and heat asthma according to different natures of pathogenic factors. Cold asthma often manifests cough with short breath, throat rale, whitish-thin-frothy sputum, and accompanied by exterior syndrome of wind and cold. Heat asthma often manifests cough, asthma with wheezing, sonorous voice and short breath, yellow is thick-sputum, fever, chest distress, showing the syndrome of phlegm and heat obstructing the lung.

At the remission stage, the disease can be divided into 3 syndromes of lung qi deficiency, spleen qi deficiency and kidney qi deficiency based on different zang-fu organs involved. Lung qi deficiency often shows pale complexion, short breath, weakness, polyhidrosis, repeated attack by cold ; spleen qi deficiency often manifests profuse sputum, epigastric fullness, poor ingestion, loose bowels, and lassitude; kidney qi deficiency often manifests susceptibility to short breath on exertion, cold body, aversion to cold, cold lower limbs, enuresis or profuse nocturia, etc..