Is yellow phlegm a sign of wind-heat or wind-cold?

Yellow phlegm is generally due to wind-heat, not wind-cold. The specific analysis is as follows:

In clinical practice, yellow phlegm is commonly seen in wind-heat感冒. Wind-heat illness usually results from internal lung heat and impaired lung qi dispersion caused by various factors. Patients typically present with fever, sore throat, cough with thick yellow purulent sputum, and a slightly yellow tongue coating. Therefore, the presence of yellow phlegm indicates wind-heat rather than wind-cold. In contrast, patients with wind-cold often experience chills, fever, clear nasal discharge, cough with white phlegm, or a thin white tongue coating.

If coughing with yellow phlegm occurs, it is recommended to seek medical attention promptly and, under a doctor's guidance, choose appropriate treatment methods. Additionally, it is important to get adequate rest, drink plenty of water, and avoid spicy or irritating foods to prevent interference with recovery.