Opioid Drug Interactions

Opioid analgesics are frequently used in critically ill patients for the treatment of moderate to severe pain from either a comorbid or an acute condition. There is a potential for clinically meaningful drug interactions in critically ill patients because of pharmacokinetic and pharmacodynamic alterations coupled with polypharmacy. An understanding of the mechanisms of drug interactions will assist clinicians in anticipating unintended consequences of drug interactions. This chapter provides a basic overview of the mechanisms of drug interactions.