Pathophysiology
Clinical meaning
The American Geriatrics Society (AGS) Beers Criteria is the most widely used explicit list of potentially inappropriate medications (PIMs) for older adults โฅ65 years. Updated every 3 years, the Beers list identifies medications with unfavorable risk-benefit ratios in older adults due to age-related pharmacokinetic changes (reduced hepatic metabolism, decreased renal clearance, increased body fat, decreased lean mass, reduced albumin) and pharmacodynamic changes (increased sensitivity to CNS-active drugs, impaired baroreceptor reflexes). Key categories: (1) PIMs to AVOID regardless of diagnosis: first-generation antihistamines (diphenhydramine โ anticholinergic, causes confusion and falls), benzodiazepines (increased fall risk, cognitive impairment, paradoxical agitation), long-acting sulfonylureas (glyburide โ hypoglycemia risk), meperidine (neurotoxic metabolite normeperidine), skeletal muscle relaxants (cyclobenzaprine, methocarbamol โ sedation, anticholinergic burden); (2) PIMs to AVOID with specific conditions: NSAIDs with CKD or heart failure, anticholinergics with dementia, benzodiazepines with falls history; (3) Drug-drug interactions: concurrent anticholinergic medications (cumulative anticholinergic burden), opioids + benzodiazepines (respiratory depression); (4) Medications requiring dose adjustment: renal-dosed medications, digoxin (target 0.5-0.9 ng/mL in elderly, not 1.0-2.0). The NP conducts systematic medication reconciliation at every visit using the Beers Criteria and anticholinergic burden...