POLYPHARMACY

Factors that contribute to polypharmacy Chronic medical conditions Female gender Multiple physicians, especially specialists Prescribing by brand and generic names Self medication with OTC medications Increased elder mobility Direct-to-the-consumer advertising Physician on call

More factors that contribute to polypharmacy Physicians are reluctant to stop a medication started by another physician End points of drug therapy are seldom set and patients are not reevaluated for the need to continue medications "Start slow, Go slow" may yield failure to raise the dose to a therapeutic level Multiple pharmacies

Adverse Drug Effects

ADEs and Drug interactions in the elderly 25% of the elderly at home. 2 to 8% of hospital admissions of all patients. If 65+, then 5 to 30% of hospital admissions. 60% of patients admitted due to adverse drug reactions were taking 11 or more drugs. Risk increases with number of drugs. Elders in the hospital get more drugs so at even greater risk of ADE while an inpatient.

Drug interactions More common in the elderly simply because they take more drugs More than 20% of adverse drug reactions in the elderly are due to drug interactions Drug-drug interactions Drug-nutrient interactions

Patient compliance problems

Patient compliance problems Morbidity and disabilities from disease Complex regimens Drug characteristics Solutions

Nonadherance and No. of Drugs

Morbidity and disabilities from disease Movement disorders Amputations Impaired vision Comprehension and memory deficits Depression or psychosis

Complex regimens Multiple medications Multiple administration times Complex administration Devices

Miscellaneous drug characteristics Taste Cost Side effects Capsule or tablet size

Altered physiology in the elderly affects medications Multiple organ system changes Pharmacodynamics Pharmacokinetics

Pharmacodynamics Altered drug receptor sensitivity Fewer receptors Receptors are less sensitive Receptors are more sensitive

Pharmacokinetics Absorption Distribution Metabolism Excretion

Absorption Reduced gastric acid and fluid- dissolution Delayed gastric emptying Reduced gastric acid - pH dependent absorption Reduced GI blood flow - absorption

Distribution Decreased total body water Decreased lean body mass Increased total body fat CHF and impaired drug delivery

Metabolism Hepatic blood flow First pass metabolism Liver enzyme system activity

Excretion Reduced renal blood flow Age related decline in blood flow CCr declines 1% per year after 40

Solutions to Problem Once a day medications Absolutely necessary medications only Education Involve family Review of medications at each visit Listening to the patient