As the elderly population in our country continues to increase, it is imperative that the bedside practitioner be keenly aware of the factors that affect pharmacokinetics and pharmacodynamics of medication administration. Refining the admission interview process to obtain accurate medication information--including alternative and OTC drugs--will help to decrease the incidence of drug interactions and ADR in the acute care setting. Appropriate monitoring of pharmacologic effects and organ function will allow the practitioner to better treat the elderly client with as few medications as possible.