Snapshot A 60-year-old man presents to the emergency room for malaise and fevers. He also reports having chills, muscle aches, fatigue, and a headache. His grandson was taken out of school for similar symptoms. He has never had a flu shot, reporting that he did not trust vaccines. His past medical history is significant for diabetes mellitus and smoking. A rapid antigen detection test for flu is positive for influenza A. He is started on a oseltamivir. (Influenza) Introduction Drugs oseltamivir (oral) zanamivir (intranasal) peramivir (IV) Mechanism of action inhibits viral neuraminidase the viral enzyme neuraminidase cleaves bonds between sialic acid moieties on the surface of the cell, increasing the number of circulating viral particles inhibition of this neuraminidase will decrease the release of viral progeny Clinical use influenza A and B treatment, if early, can shorten the clinical course and symptom duration can also be used as prophylaxis Adverse effects gastrointestinal upset Stevens-Johnson syndrome