These four characters combine to form a very literal and descriptive medical term: “To Clear Away (清) the Heat (热) and Resolve (解) the Toxins (毒).”
清热解毒 (qīng rè jiě dú) is more than just a medical term; it's a cornerstone of daily health maintenance in Chinese culture, deeply rooted in the philosophy of Traditional Chinese Medicine (TCM). The core idea is that health is a state of balance, particularly between Yin (阴) and Yang (阳). “Heat” (热) is an expression of excess Yang energy, leading to symptoms we might associate with inflammation in the West. The “toxin” (毒) is a more intense form of this pathogen, causing more severe symptoms like pus formation or high fevers. This contrasts sharply with the Western biomedical model. If you have a sore throat, a Western doctor might diagnose a bacterial infection and prescribe antibiotics to kill the specific germ. A TCM practitioner might diagnose “excess heat-toxin in the Lung channel” and prescribe herbs with a 清热解毒 function. The goal isn't just to kill a microbe but to change the body's internal environment so that the pathogen can no longer thrive. This concept is closely tied to the common household diagnosis of 上火 (shànghuǒ), or “getting internal heat.” After eating too much spicy or fried food, a person might complain of a canker sore, a dry cough, or a pimple and say, “我上火了 (Wǒ shànghuǒ le).” The immediate, culturally understood solution is to consume something with a 清热解毒 or 下火 (xiàhuǒ) (“down-putting the fire”) effect, like green tea, mung bean soup, or a bitter herbal drink called 凉茶 (liángchá).
You will encounter 清热解毒 constantly in health-related contexts in China.
The term is used seriously in a medical context but is also part of everyday, informal health vocabulary.