Individualizing Drug Therapy in the Elderly

Abstract Aging reduces one’s ability to respond appropriately to the demands of the environment due to reduced capacity for physiological adaptation to it. This process of decline varies widely among individuals. Because of these changes, elderly patients are more susceptible to polypathology and iatrogenic problems. All phases of pharmacokinetic and pharmacodynamics processes can be affected differentially by the aging processes. For example, differential renal aging occurs, nonparametric population modeling has documented the existence of an elderly subpopulation unaffected by glomerular aging, including clearance of antimicrobials remaining at the same value as for many young adult patients. Consequently, it is necessary to adjust dosages to take into account these subpopulations of old patients, as well as the location of each individual patient’s renal function within the subpopulation, in order to achieve the desired target goal with the greatest possible precision. It is necessary, in geriatrics at least as much as elsewhere, to do only minimal harm, but it is also very important to be at least as active as with young adults, especially in cases of acute pathology.