1. White and greasy tongue coating: usually indicates the presence of cold or dampness in the body, often seen in wind cold cough or phlegm dampness cough. The patient may have symptoms such as heavy coughing, clear and sparse phlegm, chills and fever, nasal congestion and runny nose.
2. Yellow and greasy tongue coating: indicates the interweaving of heat and dampness pathogens in the body, commonly seen in wind heat cough or phlegm heat cough. Patients may have symptoms such as coughing, yellow phlegm, sticky and difficult to cough, sore throat, fever and thirst.
3. Less or no coating on the tongue, with a red tongue texture: reflecting insufficient Yin fluid in the body, often seen in cough caused by Yin deficiency or dry heat. Patients may present with symptoms such as dry cough without phlegm or low phlegm but sticky, dry mouth and throat, afternoon hot flashes, and hand foot and heart heat.