Pharmacology and Aging Flashcards
What is the BEERs criteria?
Listing of drugs that should not be used in the elderly
True or false: formulations change frequently
True
What are nutraceuticals?
Herbal preps
Nutritional supplements
etc
What are the four factors of pharmacokinetics?
Absorption
Distribution
Metabolism
Elimination
True or false: amount absorbed (bioavailability) is not changed in the elderly
True
What happens to peak concentrations in the elderly? What are the exceptions to this?
Lower and delayed
Extensive first pass effect
What are the factors that affect drug absorption? (4)
Route
What taken with
Comorbidities
Gastric pH
What is the effect of divalent cations on drug absorption?
Affect absorption of fluoroquinolones
Enteral feedings interfere with what?
Absorption of some drugs
What type of drugs particularly affect absorption?
Drugs that affect GI motility
Decreased body water has what effect on drug absorption?
Lower VD for hydrophilic drugs
Decreased lean body mass has what effect on drug absorption?
Lower VD for drugs that bind muscle
Increased fat stores has what effect on drugs?
Higher VD for lipophilic drugs
Decreased plasma protein (albumin) has what effect on drugs?
Higher percentage of drug that is unbound
Generally, men or women metabolize drugs faster?
Men
What is the effect of smoking on drug clearance?
Increases clearance for some drugs
CHF has what effect on the liver?
Hepatic congestion (lowered metabolism)
What is half-life?
Time for serum [c] of drug to decline by 50%
What is drug clearance?
Volume of serum from which the drug is removed per unit of time (L/hour or mL/min)
What is the most common reason for A-fib?
HTN
Smoking increases the clearance of what drug in particular?
Theopylline
Most drugs exit the body through what route?
Kidney
What is the consequence of reduced elimination of drugs through the kidneys?
Drug accumulation and toxicity
What are four factors of the kidneys decrease in old age?
Size
RBF (GFR)
Nephrons
Renal tubular secretion
What is the first system that is usually effected d/t bad drug interactions?
GI system
What is the drug that is hard on the kidneys?
IV/oral contrast
Lower body mass does what to creatinine clearance? GFR?
Lowers
What are the two ways to determine creatinine clearance?
Measure (24 hr urine collection)
Estimate (cockroft-gault equation)
Is an 8 hour creatinine clearance acceptable?
No
What is the equation for the cockroft gault equation?
[(Ideal weight)(140-age) / 72(serum Cr)] * 0.85 if female
In pts without a significant age related decline in renal function, is CrCl under or overestimeated?
Under