PTCB Pharmacology #4 3 — Questions and Answers
Question 1: Which drug suffix indicates a "-statin" belongs to the HMG-CoA reductase inhibitor class?
- -statin
- -vastatin (Correct answer)
- -mab
- -olol
Correct answer: -vastatin
All HMG-CoA reductase inhibitors end in "-vastatin" (atorvastatin, rosuvastatin, simvastatin, pravastatin, lovastatin, fluvastatin, pitavastatin).
Question 2: Naloxone works by:
- Inhibiting opioid metabolism
- Stimulating mu-opioid receptors
- Competitively blocking opioid receptors (Correct answer)
- Increasing GABA activity
Correct answer: Competitively blocking opioid receptors
Naloxone (Narcan) is a competitive opioid receptor antagonist that rapidly displaces opioids from mu, kappa, and delta receptors, reversing respiratory depression, sedation, and analgesia within 2–5 minutes.
Question 3: Which drug is a selective serotonin-1A partial agonist used for generalized anxiety disorder?
- Diazepam
- Buspirone (Correct answer)
- Lorazepam
- Hydroxyzine
Correct answer: Buspirone
Buspirone (Buspar) is a 5-HT1A partial agonist used for GAD. Unlike benzodiazepines, it has no abuse potential, no sedation, and requires 2–4 weeks for full anxiolytic effect.
Question 4: Digoxin toxicity can be precipitated by which electrolyte imbalance?
- Hypernatremia
- Hypokalemia (Correct answer)
- Hypermagnesemia
- Hypercalcemia deficiency
Correct answer: Hypokalemia
Hypokalemia (low potassium) increases digoxin toxicity because potassium and digoxin compete for the same binding site on Na+/K+ ATPase. Diuretic-induced hypokalemia is a common precipitant of toxicity.
Question 5: Which of the following describes "tolerance" in pharmacology?
- An allergic reaction to a drug upon repeated exposure
- The need for increasing doses to achieve the same effect with repeated use (Correct answer)
- A decrease in drug concentration over time
- A change in drug receptor binding affinity
Correct answer: The need for increasing doses to achieve the same effect with repeated use
Tolerance is the reduced pharmacological response to a drug after repeated administration, requiring higher doses to achieve the original effect. It is common with opioids, benzodiazepines, and nitrates.
Question 6: Which drug class includes drugs ending in "-tidine" (e.g., famotidine, ranitidine)?
- Proton pump inhibitors
- Antacids
- H2 receptor antagonists (Correct answer)
- Anticholinergics
Correct answer: H2 receptor antagonists
H2 receptor antagonists (H2 blockers) end in "-tidine" (famotidine/Pepcid, ranitidine/Zantac, cimetidine/Tagamet). They competitively block histamine H2 receptors on parietal cells, reducing acid secretion.
PTCB Pharmacology #4 3
Which drug suffix indicates a "-statin" belongs to the HMG-CoA reductase inhibitor class?