Oseltamivir, or oseltamivir phosphate, can be taken exclusively in the absence of specific complications in the case of influenza A. The active metabolite of oseltamivir inhibits the neuraminidase activity of the influenza A virus. It is commonly used in the treatment of influenza A and B in adults and children 1 year of age and older, and in the prevention of influenza A and B in adults and adolescents 13 years of age and older. Oseltamivir alone is sufficient if influenza A is simple and is not complicated by bacterial infections, etc. If there are bacterial infections or other serious symptoms, antibiotics and symptomatic medications should be used in combination in a timely manner. The main adverse effects of oseltamivir phosphate are nausea, vomiting, headache, pain, rash, dermatitis, elevated liver enzymes, etc. It is recommended that patients use it within 48 hours of the first symptom. When suffering from influenza A, the drug should be used under the guidance of a doctor, and avoid blindly taking the drug by oneself, which may cause serious adverse consequences.