Patients who infected COVID 19 (positive COVID 19 RT-PCR from nasal swab) and pass inclusion criteria are enrolled in the study. The patients will be checked the clinical symptoms and chest x-ray by physician. They will be treated with standard treatment of COVID 19. In addition, the patients will received longan extract nasal spray (P80 spray) or placebo nasal spray for 3 days (6 times). Physician or nurse will ask for adverse events every day. After 3 days, the patients will be nasal swabbed for detecting COVID 19 infection.
