Advances in modern medicine and public health have resulted in increased longevity, which in turn has resulted in more elderly patients (arbitrarily defined as aged 65 yr or older) coming to the operating room for a variety of surgical procedures. Even in the absence of comorbidities, these patients, as compared with their younger cohorts, respond differently to various perioperative physiologic trespasses and pharmacologic interventions. In this clinical commentary, we focus on the altered pharmacologic responses elderly patients have during the perioperative period. In many instances, elderly patients are more sensitive to drugs, and for the purposes of this clinical commentary, we use the word sensitivity in its general clinical meaning, i.e., an enhanced response for a given dose of drug that might have a pharmacokinetic or pharmacodynamic explanation.