SPEX SPEX Analysis Exam 3 — Questions and Answers
Question 1: A patient taking warfarin is started on fluconazole. What pharmacokinetic interaction should the physician anticipate?
- Decreased warfarin levels due to CYP2C9 induction
- Increased warfarin effect due to CYP2C9 inhibition (Correct answer)
- No clinically significant interaction
- Decreased warfarin absorption from the gut
Correct answer: Increased warfarin effect due to CYP2C9 inhibition
Fluconazole inhibits CYP2C9, which metabolizes warfarin, leading to elevated warfarin levels and increased bleeding risk.
Question 2: Which of the following best describes the mechanism of action of metformin in Type 2 diabetes?
- Stimulates pancreatic beta-cell insulin secretion
- Inhibits hepatic gluconeogenesis via AMPK activation (Correct answer)
- Blocks alpha-glucosidase in the small intestine
- Increases renal glucose excretion
Correct answer: Inhibits hepatic gluconeogenesis via AMPK activation
Metformin primarily activates AMPK, which suppresses hepatic gluconeogenesis and improves insulin sensitivity.
Question 3: A 66-year-old man develops acute gout. His renal function is impaired (GFR 25 mL/min). Which agent is most appropriate to treat the acute attack?
- High-dose NSAIDs
- Colchicine at standard doses
- Low-dose colchicine or corticosteroids (Correct answer)
- Allopurinol
Correct answer: Low-dose colchicine or corticosteroids
In patients with renal impairment, low-dose colchicine or corticosteroids are preferred because NSAIDs and standard colchicine dosing carry significant toxicity risks.
Question 4: A patient with schizophrenia develops muscle rigidity, high fever, altered consciousness, and autonomic instability after starting haloperidol. What is the diagnosis?
- Tardive dyskinesia
- Serotonin syndrome
- Neuroleptic malignant syndrome (Correct answer)
- Acute dystonia
Correct answer: Neuroleptic malignant syndrome
Neuroleptic malignant syndrome (NMS) is a life-threatening reaction to antipsychotics characterized by hyperthermia, rigidity, autonomic instability, and altered mental status.
Question 5: Which class of antihypertensive medications is contraindicated in bilateral renal artery stenosis?
- Calcium channel blockers
- Thiazide diuretics
- ACE inhibitors (Correct answer)
- Alpha-1 blockers
Correct answer: ACE inhibitors
ACE inhibitors block efferent arteriolar constriction, reducing GFR in bilateral renal artery stenosis and potentially causing acute renal failure.
Question 6: A 55-year-old post-MI patient is prescribed a statin. What is the primary goal of this therapy beyond LDL reduction?
- Reduce triglycerides to normal range
- Prevent plaque rupture through pleiotropic effects (Correct answer)
- Increase HDL above 60 mg/dL
- Eliminate all cardiovascular risk
Correct answer: Prevent plaque rupture through pleiotropic effects
Statins provide benefits beyond LDL lowering through pleiotropic effects including anti-inflammatory actions, plaque stabilization, and endothelial function improvement.
Question 7: A physician prescribes atenolol for a patient with hypertension who also has asthma. What is the primary concern?
- Hyperkalemia from reduced aldosterone
- Bronchospasm due to beta-2 receptor blockade (Correct answer)
- Renal failure due to reduced perfusion
- Tachyarrhythmia rebound
Correct answer: Bronchospasm due to beta-2 receptor blockade
Atenolol, though cardioselective, can still cause clinically significant bronchospasm in patients with reactive airway disease.
SPEX SPEX Analysis Exam 3
A patient taking warfarin is started on fluconazole.
What pharmacokinetic interaction should the physician anticipate?