Influenza, or the flu, can be taken by people over 13 years of age who do not have the flu, but people under 13 years of age who do not have the flu cannot take oseltamivir. Oseltamivir can be used to treat influenza A and influenza B in children and adults 1 year of age and older. In addition, oseltamivir can prevent influenza A and B in adolescents 13 years of age and older and in adults. Therefore, people older than 13 years of age who do not have influenza can take oseltamivir as prescribed by their doctor to prevent influenza. If the age of people younger than 13 years old did not develop influenza, to avoid taking Oseltamivir, therefore, some people taking Oseltamivir may have nausea and vomiting, insomnia, drowsiness, rash, abdominal distension and other adverse reactions. It is recommended that patients can take Oseltamivir under the guidance of a doctor, to avoid unauthorized use of medication. In addition, people who are allergic to Oseltamivir, or people with renal insufficiency, patients under the age of 1 year are prohibited from using Oseltamivir, and breastfeeding women should use Oseltamivir with caution.