Geri Flashcards
considerations for appropriate med use in geriatric pt
-Chronic medical conditions
-Altered physiologic conditions
-Altered pharmacokinetic considerations
-Absorption
-What are the GI factors that will delay absorption of drugs and ultimately delay the onset of action?
-IM injections
-Skin changes
-Distribution
-Changes in body composition
-Total body H20 vs Total body fat
-Protein binding decreased
-Metabolism
-Altered drug metabolism due to decreased liver function
-CYP450 drug interactions
-Elimination
-Altered drug elimination
-Renally eliminated drugs:
-Antibiotics (AMG, vanco, FQs)
-Digoxin
-Ace inhibitors
-H2 blockers
-Allopurinol
-Metformin
-To name a few….
-Use of CrCl to assess renal function
overuse
-POLYPHARMACY and overdosage
-Polypharmacy strongly associated w/ ADRs & DDIs
-can increase risk of geriatric syndromes
-Average # of Rx and OTC drugs in elderly pt = 2.7 – 4.2 meds (when taking a hx – remember to always ask about OTCs and herbals)
-Nursing home pts:
-Average of 6.69 meds
-27% - 9 or more meds
-Polypharmacy (use of 1+ unnecessary meds) – occurs in 55-59% of elderly outpatients
-Average geriatric pt receives 12-17 RXs per year
-60% office visits end w/ RX
-15% hospital admissions due to Adverse Drug Event
inappropriate use
-Prescribing meds outside bounds of accepted medical standards.
-Prescribing drugs whose use should be avoided bc their risk outweighs their potential benefit
-Beer’s Criteria
-Sample of drugs on Beer’s List
-Analgesics (Ketorolac, Meperidine)
-TCAs
-SSRIs w/ MAO-Is
-Antihistamines
-Antihypertensives (alpha-1 blockers, clonidine, methyldopa)
-Antipsychotics
-Long-acting Benzodiazepines
-Digoxin
-Amiodarone
-NSAIDs
-Anticholinergics
-Cimetidine
-Hypnotics
-Muscle Relaxants
-Factors contributing to inappropriate drug use in elderly
-Multiple disease states
-Multiple health-care providers
-Use of multiple pharmacies
-Time limitations during office visits
-OTC medication use
-Dietary intake
underuse
-Omission of drug therapy that is indicated for the treatment or prevention of a disease or condition.
-Sub therapeutic dosages
medication nonadherence
-50% of elderly pts nonadherent
-similar rates to younger groups when # of drugs taken by groups is similar
ADRs and DDIs
-Common Drug Interactions in Long-Term Care
-Warfarin-NSAIDs
-Warfarin-Sulfa Drugs
-Warfarin-Macrolides
-Warfarin-Quinolones
-Warfarin-Phenytoin
-ACE-I and K+ supplements
-ACE-I – spironolactone
-Digoxin-Amiodarone
-Digoxin-Verapamil
improving med use in elderly pt
-Be cognizant of chronic medical conditions, altered physiologic conditions and altered pharmacokinetics that will affect medication use in the geriatric patient
-Provide a comprehensive geriatric assessment of your patient including an appropriate H&P
-Use the Medication Appropriate Index: (Questions to ask about each individual med)
-Is there an indication for each drug
-Is the drug effective for the condition?
-Is the dosage correct?
-Are the directions correct?
-Are the directions practical?
-Are there clinically significant DDIs?
-Are there clinically significant drug-disease or drug-condition interactions?
-Is there unnecessary duplication with other drugs?
-Is the duration of therapy acceptable?
-Is the drug the least expensive alternative compared with other of equal utility?
dosing elderly pts
-consider chronic conditions:
-arthritis- cant open bottles
-HTN- DDI/ADRs
-hearing loss- compliance
-delirium- confusion, compliance
-depression (20%)
-altered ADLs
-altered physiologic conditions
-altered pharmokinetics
physiologic changes in elderly
-Changes in body composition (decrease total body H20)
-CVS - decrease sensitivity to beta adrenergic stimulation
-CNS – memory/cognitive impairment
-Gait & Mobility – altered balance
-GI changes (decrease saliva, constipation)
-GU changes (incontinence)
-decrease hepatic function
-decrease renal function
-senses- visual changes, cataracts, glaucoma
-affects pharmokinetics and pharmodynamics of meds
pharmacokinetics: absorption: elderly
-increase gastric pH
-decrease intestinal blood flow
-decrease intestinal mobility
-decrease intestinal surface area
-decrease gastric emptying rate
-Altered nutritional status
-increase use of OTC drugs
-ALL delay absorption & delay onset
-decrease muscle mass- painful IM inj
-skin changes affect topicals:
-decrease hydration
-decrease surface lipids
-decrease peripheral circulation
pharmakinetics: distribution: elderly
-TEST
-changes in body composition affect drug distribution:
-decrease total body H2O
-decrease lean body mass
-increase body fat
-decrease serum albumin
-highly protein bound drugs
pharmakinetics: metabolism: elderly
-decrease hepatic mass and volume
-decrease hepatic blood flow
-decrease hepatic function
-can affect drug metabolism by the liver
pharmakinetics: renal elimination: elderly
-decrease functional cells in kidney
-decrease renal blood flow
-decrease GFR (creatinine clearance)
-renally eliminated drugs:
-AMG, vancomycin, quinolones
-PCN, CPS
-digoxin, metformin, allopurinol, H2 blocker
-ACE inhibitors, lithium
estimating creatinine clearance
-Cockcroft-Gault equation
CrClmen = (140-age) x IBW / Scr x 72
CrClwomen = CrClmen x 0.85
IBWmen = 50kg + (2.3 x inches>5ft)
IBWwomen = 45.5 kg + (2.3 x inches>5ft)
pharmacodynamic changes
-decrease baroreceptor sensitivity
-Orthostatic hypotension w/ VD, TCA, PTZ
-CNS changes
-increase risk of tardive dyskinesia w/antipsychotics
-increase sensitivity to anticholinergics
-Receptor alterations
