Pharmacokinetic changes in critical illness. 
Physiologic alterations in critically ill patients can significantly affect the pharmacokinetics of drugs used in the critically ill patient population.  Understanding these pharmacokinetic changes is essential relative to optimizing drug therapy.  This article outlines the major differences seen in the absorption, distribution, metabolism, and excretion of drugs in critically ill patients.  Important strategies for drug therapy dosing and monitoring in these patients are also addressed.