Huo Xiang Zheng Shui and Cephalexin should not be taken together because Huo Xiang Zheng Shui contains alcohol and Cephalexin can interact with alcohol, which can cause adverse reactions in patients. In clinical terms, it is called disulfiram reaction, and patients may experience nausea, vomiting, dizziness, headache, and in severe cases, they may also have breathing difficulties and other symptoms, and it may even be life-threatening. It is mainly due to the interaction between certain cephalosporins and alcohol, and cephalosporins can inhibit the metabolism of alcohol. Alcohol is metabolized into acetaldehyde by the corresponding enzymes in the body, and then acetaldehyde is metabolized into acetic acid and finally excreted out of the body. The intermediate metabolite acetaldehyde, which is a substance that causes the occurrence of intoxication reaction, can be inhibited by cephalosporins to metabolize acetaldehyde into acetic acid, thus causing the accumulation of acetaldehyde in the body and the occurrence of severe intoxication reaction. Therefore, it is not recommended that patients use cephalosporin during the use of Huo Xiang Zheng Shui.