The dosage of oseltamivir phosphate granules varies in different groups of people, such as in adults and adolescents over 13 years of age for the treatment of influenza the dosage is 75 mg/dose, 2 times/day, for prevention is 1 time/day; children 1 year old and over 1 year old for the treatment of influenza A and B according to the weight of the drug to determine the dosage. The dosage of oseltamivir phosphate granules for children weighing up to 15 kilograms is 30 mg/dose, for those weighing 15-23 kilograms the dosage is 45 mg/dose, for those weighing 23-40 kilograms the dosage is 60 mg/dose, and for those weighing more than 40 kilograms the dosage of the drug is the same as that for adults, which is 75 mg/dose, all of which is 2 times a day. Oseltamivir phosphate granules may cause nausea, vomiting and other adverse reactions, and is contraindicated for those who are allergic to its ingredients; note that this product is not a substitute for influenza vaccine. This product should be taken under the guidance of clinicians, do not self-medication.