Recently, many Shanghai citizens received Lianhua Qingwen capsule or granule. Some people think covid-19 can prevent new crown pneumonia. Some people think, "don't take medicine without illness". So, can Lianhua Qingwen be used as a preventive drug? Covid-19 has been recommended by the National Health Committee for many times, and is written in the new crown pneumonia diagnosis and treatment plan. In March 15th this year, the newly released New Coronavirus pneumonia diagnosis and treatment plan (trial version ninth) clearly stated that light and ordinary patients in medical observation period or clinical treatment period (confirmed cases) recommend Lianhua Qingwen capsule (granule) as a therapeutic drug. However, covid-19 can prevent the new crown pneumonia. Several doctors also clearly pointed out that Lianhua Qingwen is a therapeutic drug, not a preventive drug. Oral administration in advance can not prevent Xinguan. If there are no symptoms, it is not recommended. Fang Bangjiang, director of the emergency medicine department of Longhua Hospital Affiliated to Shanghai University of traditional Chinese medicine, said that in general, Lianhua Qingwen capsule is only suitable for patients with mild fever and patients with common pneumonia, but it is not suitable for preventive medicine. Chinese herbal medicine contains a lot of electrolytes. It is not suitable for people with poor spleen and stomach function, gastric ulcer and poor liver and kidney function. Inappropriate preventive measures need attention. Fang Hong, director of traditional Chinese medicine prevention and health care department of Longhua Hospital, also reminded that Lianhua Qingwen capsule is a therapeutic drug for patients with Xinguan. It is not a preventive drug. Oral administration in advance can not prevent Xinguan. Fang Hong said that if the antigen is positive but the nucleic acid has not been reviewed, and there are no symptoms such as fever, sore throat and cough, it is not recommended to take it. If you have fever, chills, muscle soreness, nasal congestion, runny nose, cough, headache, dry throat, sore throat and other symptoms, you can take Lianhua Qingwen. (outlook new era)