Elder medications Flashcards
Describe the Term Pharmacokinetics
“what the body does with the drug” Absorption Distribution Metabolism Excretion
Describe the Term Pharmacodynamics
“what the drug does to the body”
Receptors
Blocked
Stimulated
Drug interactions that slow absorption
Use of combinations of drugs wherein one drug affects absorption of the other i.e. Antacids/Ca/Mg/Al ions bind to object drug decreasing effect of same
Free fraction effect: drugs binding ++ to protein
Decreased Albumin production/aging liver=rise in free fraction in blood=increase in toxic side effects i.e. malnutrition, uremia; diabetes; acute nephrotic syndrome; surgery
Slowed liver metabolism
Aging causes liver function to diminish i.e drug catabolization declines
Active drug or metabolites remain in body longer i.e. long acting benzodiazepines (Diazepam/Valium)
May result in excessive sedation
Renal function decline
Renal function declines with age i.e. creatinine clearance declines 10% q decade after 40yrs
Creatinine clearance 30ml/min or below =risk of accumulation of drug/metabolites nephrotoxic to kidney function i.e. Aminoglycosides ( Gentamycin)
Initial renal function level and ongoing Peak and Trough level monitoring essential to prevent irreversible kidney damage /hearing loss/balance disturbances
Rational vs. irrational polypharmacy
Rational->conscientious, minimal use of multiple drugs +diligent pt. follow-up
Irrational-> inappropriate use of multiple drugs-> risks outweigh benefits
Roots of irrational polypharmacy
Prescriber hesitates to d/c meds. pt. has been taking long time-> adds on more meds
Prescriber orders meds. to alleviate adverse reactions to other meds
Pt. influenced by anecdotal reports re benefits of certain meds
Alternative pharmacotherapy
40% or more adults use alternative pharmacotherapy ie herbal remedies unbeknownst to HC providers
Why? Many people believe ‘natural’/alternative medications bought form a reputable source =safe
Commonly used examples: gingseng, ginko biloba,garlic, St. John’s wort however, adverse interactions with some medications ie anticoagulant Warfarin; St. J’s wort/Digoxin level depletion etc.
Potentially inappropriate medication use in the elderly
Beers Criteria-updated in 2015 by American Geriatrics Society
Intended for:
use in all ambulatory, acute, institutionalized settings
Adults 65 yrs and older
Palliative and hospice settings excluded
Improve care of older adults by reducing exposure to PIM’s (potentially inappropriate medications)
PIMS and drug/drug interactions in the elderly
Anticoagulants Anticholinergics Cardiac glycosides Antihypertensive agents Antimicrobials Antipsychotics, anxiolytics, antidepressants, benzodiazepines NSAID’s Laxatives Antacids Long acting oral hypoglycemics Opioid analgesics
Nurses role
Complete a thorough history including drug/alcohol consumption
Ensure medication reconciliation complete on admission, transfer, and discharge (herbs, OTC, vitamins)
Know the therapeutic aim of the drug and how it will be measured
When is the outcome to be reviewed?
What adverse effects might be expected and their significance?
How will the drug be monitored? Ie lab values
Teach about medication hazards
Institute non pharmacological approaches prn
Individualize patient education to patient/family (oral/written)
principles of geriatric prescribing
Titrate dosage with pt. response i.e. “start low and go slow’
Simplify therapeutic regimen
Encourage regular pharmacy med reviews
Encourage use of one pharmacy only
Consider safest dispensing ie med machine, blister packs
Monitor compliance
Avoid pharmacology whenever possible try nonpharmacological approaches
