CCP Geriatric Pharmacology 2 — Questions and Answers
Question 1: Which pharmacokinetic change is most consistently observed in elderly patients due to decreased lean body mass?
- Increased volume of distribution for lipophilic drugs
- Decreased volume of distribution for lipophilic drugs (Correct answer)
- Increased renal clearance of hydrophilic drugs
- Decreased protein binding of acidic drugs
Correct answer: Decreased volume of distribution for lipophilic drugs
Decreased lean body mass in elderly reduces the volume of distribution for lipophilic drugs, potentially increasing plasma concentrations.
Question 2: An 80-year-old with a normal serum creatinine of 0.8 mg/dL is prescribed a renally cleared antibiotic. What is the most appropriate next step?
- Use the creatinine value to confirm normal renal function and give standard dosing
- Calculate CrCl using Cockcroft-Gault to account for reduced muscle mass (Correct answer)
- Increase the dose because low creatinine indicates good renal function
- Switch to a hepatically cleared antibiotic to avoid renal concerns
Correct answer: Calculate CrCl using Cockcroft-Gault to account for reduced muscle mass
A low serum creatinine in elderly often reflects reduced muscle mass, not good renal function; Cockcroft-Gault CrCl calculation is essential.
Question 3: Which agent is considered potentially inappropriate per the Beers Criteria for older adults due to the risk of hypoglycemia?
- Metformin
- Glipizide
- Glyburide (Correct answer)
- Sitagliptin
Correct answer: Glyburide
Glyburide is a long-acting sulfonylurea with active metabolites that accumulate in elderly, significantly increasing hypoglycemia risk.
Question 4: What is the primary reason first-pass metabolism is often reduced in elderly patients?
- Increased gastric acid production
- Decreased hepatic blood flow and liver mass (Correct answer)
- Enhanced CYP3A4 enzyme activity
- Increased intestinal motility
Correct answer: Decreased hepatic blood flow and liver mass
Aging reduces hepatic blood flow and liver mass by up to 40%, decreasing first-pass extraction and increasing oral bioavailability of high-extraction drugs.
Question 5: An elderly patient on warfarin begins taking trimethoprim-sulfamethoxazole for a UTI. What is the expected outcome?
- INR decreases due to enzyme induction
- INR increases due to CYP2C9 inhibition (Correct answer)
- No significant interaction is expected
- Warfarin absorption is reduced
Correct answer: INR increases due to CYP2C9 inhibition
TMP-SMX inhibits CYP2C9, the primary enzyme metabolizing warfarin's S-enantiomer, leading to elevated INR and bleeding risk.
Question 6: Which of the following best describes the concept of 'prescribing cascade' in geriatric patients?
- Adding medications in a stepwise protocol to treat a single disease
- Prescribing a new drug to treat an adverse effect of an existing drug (Correct answer)
- Reducing polypharmacy by deprescribing unnecessary medications
- Using lower doses of all medications due to age-related changes
Correct answer: Prescribing a new drug to treat an adverse effect of an existing drug
A prescribing cascade occurs when a drug's adverse effect is misinterpreted as a new medical condition, leading to prescription of an additional drug.
Question 7: In a nursing home patient with dementia and behavioral symptoms, which class of medications carries a Black Box Warning for increased mortality risk?
- SSRIs
- Benzodiazepines
- Atypical antipsychotics (Correct answer)
- Cholinesterase inhibitors
Correct answer: Atypical antipsychotics
Atypical antipsychotics carry an FDA Black Box Warning for increased risk of death when used in elderly patients with dementia-related psychosis.
CCP Geriatric Pharmacology 2
Which pharmacokinetic change is most consistently observed in elderly patients due to decreased lean body mass?