Geriatrics RX Flashcards
What Case Study marked reform for SNF and RX for elderly
Beers Criteria
Residents prescribed 8.1 medications/month
More than half received antipsychotic
28% received sedative hypnotics
benzodiazepines, 30% received long acting forms.
Changes in life style, polydrug therapy, increased use of “alternative therapies”, multiple disease conditions and psychiatric changes makes dose adjustment even more important.
Geriatric definition
over 75 years old.
Altered pharmacokinetics in the geriatric patient
What can increase adverse responsed to CNS drugs?
Receptor numbers and/or affinity for the receptors change
Post-receptor factors can change
Homeostatic mechanisms may be altered.
High rate of ADRs in the elderly
High rate of ADRs in the elderly
- they take more drugs
- prescription errors due to disregard of the above changes in elderly
- multiple physicians and PAs do not communicate
- INC use of OTCs
- DEC compliance due to higher number of daily drugs
- INC dosing increases chances for errors
Antimicrobials, bacteriostatic drugs, renal clearance and host immune system
beta lactams, aminoglycosides
In geriatric what are concerns with sedative-hypnotics?
Geriartics cant sleep- Bmed maybe they don’t need that much
t1/2 INC > 60 - 70y d/t DEC renal function (CC) and liver function.
TRANSFORMED into active metabolites = toxicity
ataxia….increased falls and bone fractures.
***Lorazapam and oxazepam less effected DOES NOT CONVERT TO METABOLITE
Opioids and respiratory depression, morphine etc.
erly are more sensitive to the respiratory depression induced by opioid drugs.
Low dose to start with adjustments upward based on response is
Ache inhibitors and Alzheimer’s disease, donepezil and azole antifungals
Donepezil, rivastigmine and galantamine are newer less toxic CNS AchE inhibitors.
Co-administered drugs that inhibit CYP450 enzymes required for AchE inhibitor drug biotransformation should be avoided (ketoconazole antifungal).
Systolic hypertension frequency increased in the elderly
Systolic pressure increases with age especially in Western countries with high dietary salt intake.
“late-onset systolic hypertension” treated with diet, salt reduction, weight reduction encouraged.
Diuretics in low doses to avoid hypokalemia, hyperglycemia, increased Cp uric acid levels.
All the general cautions about altered pharmacokinetics in the elderly apply when treating systolic hypertension.
Digoxin and CC
High incidence of heart failure in the elderly often treated with digoxin.
Digoxin has a narrow TI of 1-2 ng/mL
Impaired CC requires dose adjustment.
Narrow TI increases risk of toxicity (forget dose, take double dose etc)
Digitalis toxicities occur more frequently in the elderly (arrhythmias, delirium, visual changes and endocrine abnormalities).
antimicrobials
Decreased host defense mechanisms in the elderly increases the incidence of infections.
Most commonly used antibiotics are cleared through renal mechanisms. CC dose adjustment required for the beta lactams and the aminoglycosides.
Aminoglycosides cause cranial nerve damage with loss of hearing and renal failure. Constant use of Cp levels and dose adjustment required.
Osteoporosis induced by corticosteroids, NSAIDs induce renal failure (why?)
Osteoarthritis is common disease in the elderly.
Corticosteroids induce osteoporosis which results in fractures.
NSAIDs both COX-1 and COX-2 selective and nonselective (aspirin, ibuprofen, naproxin) can cause renal damage after prolonged high dose use.
Case Study 75-year old on multiple drugs and presents with renal failure
**renal failure due to prolonged NSAID use
GERI take like candy b/c they hurt.
BUt they shut down prostaglandins for normal kidney fx.
TX- W/D digoxin and ibuprofen
reduce diuretic to 12.5 mg/d
switch from aspirin to acetaminophen
Seven Points about prescription writing for the elderly
1- consider lower cost alternative drugs
2- Caution against stopping an ABX by the patient due to relief
3- Integrate drug choices with what other care-givers to help avoid ADRs.
4- Pt take herbal, think not “drugs” and are safe. Ask all things taken. Pts will not disclose for various reasons.
(5) containers are often “patient proof” in patients with arthritis.
6) Pts with tremor, arthritis, visual problems can not self-administer correctly. Too small writing, measure
(7) reduce the#of drugs being taken, co-ordinate dosing to reduce number of different times required.
Seven steps to safe prescription writing for the elderly
1-“Start low and go slow” 1/2 titrate to the desired effect.
- Prescribe the fewest drugs possible and use the simplest dosing regimen.
(3) Patient instruction and education about dose and dosing schedule require more time than expected.
(4) Keep cost in mind. Work with patient’s on fixed income and limited or no insurance.
(5) Review patient’s drug list periodically. Have patient bring all drugs. OTC and herbal medicines to office once a year.
(6) Provide patient with a portable prescription record to take to other physicians. This helps avoid drug-drug ADRs and duplicaiton.
(7) Make home health nurses and aides aware of your need to know about any ADRs observed in your patient.
