Prevention of iatrogenic illness: adverse drug reactions and nosocomial infections in hospitalized older adults.

Adverse drug reactions and nosocomial infections are two important aspects of iatrogenesis in hospitalized older adults. Adverse drug reactions are related to changes in pharmacodynamics and pharmacokinetics that occur with aging as well as polypharmacy. Strategies for limiting iatrogenesis due to medications are discussed. Nosocomial infections continue to complicate older inpatients' care despite advances in understanding and treating institutional infections. In particular, urinary tract infections, nosocomial pneumonias, and Clostridium difficile-associated diarrhea are potentially preventable.