Principles of Anti-Infective Therapy

Anti-infective agents treat infection by suppressing or destroying the causative microorganisms. Antibiotics derive from natural substances and antimicrobials from synthetic ones -- the terms are now used interchangeably. They should be used only when a significant infection is diagnosed or strongly suspected, or an established prophylactic indication exists.

Before therapy, obtain a Gram stain, culture, and susceptibility tests (without contaminating the specimen). Choice of agent depends on the drug's pharmacological properties, spectrum of activity, and host (patient) factors.

📖 “Anti-infectives suppress/destroy microorganisms. Antibiotics (natural) vs antimicrobials (synthetic), used interchangeably. Use only for diagnosed/suspected infection or prophylaxis. Gram stain, culture, susceptibility first. Gram-positive = blue/purple; gram-negative = red/pink.”