prescribing in the elderly
DESCRIPTION
Carolyn Glover Registered Pharmacist February 28, 2013. Prescribing in the elderly. Objectives. Understand pharmacodynamics and pharmacokinetics of the elderly Identify high risk patients and high risk drugs Discuss relevance of drug interactions and polypharmacy. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/1.jpg)
PRESCRIBING IN THE ELDERLY
Carolyn Glover Registered PharmacistFebruary 28, 2013
![Page 2: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/2.jpg)
Objectives Understand pharmacodynamics and
pharmacokinetics of the elderly Identify high risk patients and high risk
drugs Discuss relevance of drug interactions
and polypharmacy
![Page 3: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/3.jpg)
Age related Physiologic changes Endocrine CNS Cardiovascular Skeletal Genitourinary Immune system Pulmonary Liver
Oral Sensory Renal GI Body composition
![Page 4: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/4.jpg)
Age related changes Increasing comorbidities Polypharmacy Aging results in physiologic changes of
absorption distribution metabolism elimination of drugs
![Page 5: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/5.jpg)
Absorption Gastric PH increases with age Decreased absorptive surfaces and
decreased visceral blood flow Decreased gastric emptying Leads to
increased contact time with stomach-GI bleeds with NSAIDS
Increased PH reduces absorption of medications needing acidic environment
(ie calcium, ketoconazole, iron)
![Page 6: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/6.jpg)
Distribution Increase in adipose tissue leads to increase
in fat soluble medications (benzodiazepines, propanolol, barbituates)
Decrease in body water, leading to lower volume for water soluble medication (increased levels of lithium, gentamicin, ethanol)
Possible reduction is albumin can increase drugs like phenytoin, digoxin, warfarin, theophylline
![Page 7: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/7.jpg)
Metabolism-Hepatic Changes Decrease in hepatic flow as well as
decrease in liver size leads to decrease clearance and increased half life for oxidative metabolism drugs
Medications affected- propanolol, diazepam, morphine
Elderly take more drugs which are competing for the same P450 enzymes to metabolize leading to drug interactions
![Page 8: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/8.jpg)
Elimination Decreased renal blood flow and decreased
renal mass GFR and tubular secretory function decreases
with age Creatinine production deceases with decreased
muscle mass making CrCl more unpredictable HCTZ, atenolol, digoxin, lithium etc. Titrate to effect rather than empirically dosing Look for trending eGFR to make decisions
instead of based on a single Scr result
![Page 9: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/9.jpg)
Pharmacodynamics (Target Organ Sensitivity to Drug)
Can have change in receptor binding, decrease in # of receptors or altered action of receptors
Decrease in receptor response will decrease effect of adrenergic meds (leading to less bradycardia with beta blockers)
Increase in receptor response increases effect and toxicity of morphine
Increase receptor response to anti-cholinergics increases confusion, constipation and urinary retention effects
![Page 10: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/10.jpg)
Who are High risk Patients? Patients with multiple prescribers and/or
multiple co-morbidities Over 85 years (30% of >85yrs had
claims for >10drug classes) More than 6 daily medications Low BMI ( < 22) Cognitive impairment Decreased renal function
![Page 11: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/11.jpg)
Compliance Issues= High Risk Patients Pill burden is the total # pills/day leads
to non-compliance or poor compliance Non compliance can lead to significant
withdrawal events-ie tachycardia with Beta blockers; rebound hyperacidity with PPI; rebound insomnia with benzos
![Page 12: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/12.jpg)
Non Compliance leads to Hospitalization
20% of prescriptions written for seniors are not filled
80% compliance problems due to perception that drug is unnecessary or that it will lead to ADR
Also could be forgetfulness, difficulty hearing or seeing instructions, inability to understand the purpose of the medication, trouble opening vials
![Page 13: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/13.jpg)
What are dangerous Drugs? Survey found 20% of hospital admissions
were due to drug related events 40% of delirium is drug induced Classes of dangerous medications
implicated include psychotropics, NSAIDS, hypoglycemics, diuretics, digoxin, warfarin and anticholinergics (see anticholinergic list in Rxfiles under “dementia”)
![Page 14: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/14.jpg)
How to use High Risk Drugs Caution with these classes of medications
Does the patient even need the drug?Is this the best drug in its class for the elderly?Can you modify the titration to avoid ADRs?
Medications that contribute to hospitalization=warfarin + Insulin + oral antiplatelets + oral Hypoglycemics = 70% of the drug related ER visits
![Page 15: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/15.jpg)
Misuse of Drugs Best practise guidelines are encouraging medication
regimes that are more complex, leading to polypharmacy
Elderly patients have multiple chronic conditions which lead to multiple prescribers, increasing ADRS
Overuse of a particular medication in an effort to improve symptoms resulting in sometime exponential side effects (ie. benzos for sleep)
Underuse of medications from patient (ie. pain medication prescribed as PRN) or from prescriber (warfarin due to hemorrhagic concerns)
![Page 16: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/16.jpg)
Misuse of Drugs Continued.. Most Canadians >80yrs have 2 or more
conditions that require preventative medications like statins, aspirin, beta blockers, ACE inhibitors, anti-hypertensives, bisphosphonates, vitamin D
Patients take medications (prescribed or OTC) in response to symptoms the patient has, often it is an ADR to the preventative medications
![Page 17: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/17.jpg)
Common Prescribing Cascades Ibuprofen hypertension antihypertensive
edema diuretic potassium Gabapentin edema diuretic potassium Lithium tremor propranolol depression
SSRI Amitriptyline cognition donepezil Narcotic constipation sennosides diarrhea
![Page 18: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/18.jpg)
Drug Interactions Drug interactions can require an adjustment in 1
medication, discontinuation of 1 medication or monitoring but continuing with both meds
European study found most common DI adjustments were:Warfarin + ABX(risk of bleed) Warfarin + phenytoin (risk of bleed and phenytoin
toxicity)ACE/ARBS +/- spironolactone +/- potassium
supplements (hyperkalemia)Digoxin + amiodarone/verapamil causing digoxin
toxicity
![Page 19: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/19.jpg)
Significant Drug Interaction Hospital Admissions
Digoxin + furosemide ACE/ARB + potassium supplements Acetaminophen + warfarin
Increase in Adverse events associated when more than 6 meds
DON’T forget to ask about the OTCs that elderly are often taking
![Page 20: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/20.jpg)
Polypharmacy More than 6 medications Any symptom in an elderly patient
should be first considered a drug side effect until proven otherwise. This avoids prescribing further medications
![Page 21: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/21.jpg)
Conditions That Could Result from Polypharmacy QT prolongation Serotonin syndrome Delirium/dementia Xerostomia Falls and unsteadiness
![Page 22: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/22.jpg)
Lack of Evidence Limited info in literatures/studies on drugs
used for patients >80yrs since meds are not generally tested in this population
3/155 RCTs are exclusively with the elderly
Exclusion criteria leads to studying only healthy, older subjects which is NOT the real world patients we deal with every day
![Page 23: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/23.jpg)
Coroner’s report 83yr old death In 2006, AS fell, fractured wrist, ribs and pelvic fracture needing
escalating doses of oxycodone Was on high dose oxycodone from fall 2006.Admitted to retirement
home in 2007-developed abdominal distention, nausea, diarrhea. Txt= loperamide, dimenhydrinate.
Transferred to hospital and found to have heart failure TXT=furosemide, dimenhydrinate, morphine, scopolamine, fleet enema
Died 15hrs after hospital arrival-toxicologic reported supratherapeutic levels of oxycodone, diphenhydramine, morphine, lorazepam acetaminophen and chlorpheniramine
NOTE: heart failure impairs metabolism increasing ADR NOTE: Constipation may present as diarrhea –loperamide should
not be given when pt on opioids NOTE: number of OTC drugs listed
![Page 24: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/24.jpg)
Strategies Use screening tools
Beers criteriaSTOPP/START criteria
Identify prescribing cascadesEngage in “deprescribing”
Appropriateness- Indicated, Compliance, Effective, Safe (ICES)
Calculate and reduce pill burden Adjust guidelines for frail elderly
![Page 25: Prescribing in the elderly](https://reader035.vdocuments.us/reader035/viewer/2022070420/56815fc0550346895dcebbe6/html5/thumbnails/25.jpg)
Find the Balance