NR 567 Advanced Pharmacology for the Adult-Gerontology Acute Care Nurse Practitioner (AGACNP) Exam with Questions and Answers

It covers key domains which include Advanced Pharmacokinetics, Advanced Pharmacodynamics, Drug Classes in Acute & Critical Care and Pharmacology in Special Populations. Mrs. Thompson is a 72 year old woman with congestive heart failure and chronic kidney disease (eGFR = 28 mL/min). She was admitted for exacerbation of dyspnea and started on a new antibiotic that is primarily renally eliminated. After two doses, she complains of nausea and dizziness. Vital signs show a heart rate of 98 bpm and blood pressure of 90/58 mm Hg. Labs reveal rising BUN/creatinine. She has no known hepatic dysfunction. What is the most likely pharmacokinetic explanation for her adverse effects? a. Reduced renal elimination leading to increased plasma drug concentration b. Increased volume of distribution due to fluid overload c. Enhanced hepatic metabolism producing toxic metabolites d. Increased first pass effect decreasing drug bioavailability Correct Answer : a. Rationale: In patients with impaired renal function like Mrs. Thompson, drugs that are primarily renally excreted accumulate, increasing plasma concentrations and risk of toxicity. Reduced elimination prolongs half life, especially for renally cleared drugs. Increased Vd does not explain acute toxicity here, and first pass or enhanced hepatic metabolism are unrelated to declining renal elimination. A 65 year old man with a history of alcoholic cirrhosis presents with confusion and new onset tremor. He was recently started on a benzodiazepine for anxiety. His medication list reveals no renal insufficiency but significant edema and hypoalbuminemia. Which pharmacokinetic change most accounts for his increased drug effect? a. Decreased plasma protein binding resulting in increased free drug b. Enhanced renal clearance increasing active metabolite removal c. Reduced absorption from gastrointestinal edema d. Increased first pass metabolism through hepatic hyperperfusion Correct Answer : b. Rationale: In cirrhosis, reduced plasma protein (especially albumin) increases free fraction of highly protein bound drugs, enhancing effect. Additionally, decreased hepatic metabolism increases drug exposure. Renal clearance increase is unlikely here, and first pass effects typically decrease in liver disease, not increase.