Many geriatric patients are “walking chemistry sets” because they are prescribed multiple drugs in complex dosage schedules. Polypharmacy is common in older people because of the presence of multiple chronic medical conditions, the proven efficacy of an increasing number of drugs for these conditions, and practice guidelines that recommend their use. Polypharmacy has been defined variably in the literature with the threshold varying between 5 and 10 routine medications. This may be the result of older people seeing multiple prescribing clinicians who do not communicate with each other and a lack of a comprehensive medication list either electronically or in hard copy.
The nature of drug therapy in managing chronic disease has changed greatly. Many conditions can be better controlled, but at a cost. In many instances, however, complex drug regimens are unnecessary; they are costly and predispose to nonadherence and adverse drug reactions. Many older patients are prescribed multiple drugs, take over-the-counter drugs, and are then prescribed additional drugs to treat the side effects of medications they are already taking. This scenario can result in an upward spiral in the number of drugs being taken resulting in polypharmacy.
Several important pharmacological and nonpharmacological considerations influence the safety and effectiveness of drug therapy in the geriatric population. This chapter focuses on these considerations and gives practical suggestions for prescribing drugs for older patients. Drug therapy for specific geriatric conditions is discussed in several other chapters throughout this text.
NONPHARMACOLOGICAL FACTORS INFLUENCING DRUG THERAPY
Discussions of geriatric pharmacology frequently center on age-related changes in drug pharmacokinetics and pharmacodynamics. Detailed reviews of these areas are provided in the Suggested Readings section at the end of the chapter. Although these changes are often of clinical importance, nonpharmacological factors can play an even greater role in the safety and effectiveness of drug therapy in the geriatric population. Several steps make drug therapy safe and effective (Fig. 14-1). Many factors can interfere with these steps in the geriatric population; most of them come into play before pharmacological considerations arise.
Factors that can interfere with successful drug therapy.
Effective drug therapy requires accurate diagnoses. Many older patients underreport symptoms; patient complaints may be vague and multiple. Symptoms of physical diseases frequently overlap with symptoms of psychological illness. To add to this complexity, many diseases present with atypical symptoms. Consequently, making the correct diagnoses and prescribing the appropriate drugs are often difficult tasks in the geriatric population.
Healthcare professionals tend to treat symptoms with drugs rather than to evaluate the symptoms thoroughly. Because older patients often have multiple problems and complaints and consult several health-care professionals, they can readily end up with prescriptions for several drugs. Moreover, older patients or their family members sometimes exert pressure on health-care professionals to prescribe ...