Antiflu 75 is not a vaccine. It only treats and prevents the flu infection. This medicine can be taken with or without food. Your doctor will decide the correct dose and duration for you based on your age, weight and health.Patients (especially children and adolescents) taking ANTIFLU 75MG should be closely monitored for any changes in behavior, such as abnormal behavior, delusions, hallucinations, agitation, anxiety, or nightmares, and should inform their doctor immediately in the event of an outcome. fatal. Other common side effects are nausea, vomiting, stomach pain, stomachache, and headache. These side effects are usually temporary and resolve with continued treatment.