Pharmacokinetics and pharmacodynamics: optimal antimicrobial therapy in the intensive care unit.

This article reviews the principles of antimicrobial pharmacokinetics and pharmacodynamics in the context of the ICU for the most commonly used antibiotics. For therapy to truly be efficacious, the regimen must be effective against the organism, but not harmful to the patient. We review how optimization of chemotherapy requires a careful balancing of efficacy against toxicity when selecting dose and dose schedules. In addition, we discuss the importance of considering concentrations at the site of infection and how dose optimization can help suppress resistance emergence and preserve our antimicrobial armamentarium for the future. Finally, we examine combination chemotherapy and strategies for optimizing the administration of multiple agents.