Antibiotics cannot treat viral infections — not colds, not flu, not COVID-19. This guide explains exactly why: antibiotics target bacterial biology, and viruses have none of it. We debunk the 5 most persistent myths about antibiotics and viral illness, explain the antibiotic resistance crisis, cover what actually works for viral infections, and list the antivirals that do exist for specific viruses.

Azithromycin — the famous Z-Pack — was America's 64th most prescribed drug in 2023, with 10 million+ prescriptions. But in 2026, two important warnings every patient should know: a March 2026 UCSF study confirmed even one day of Azithromycin triggers antibiotic resistance changes, and NEJM data confirms a real cardiac risk in high-risk patients.