Pharm.D. Doctor of Pharmacy Clinical Pharmacology and Therapeutics 2 — Questions and Answers
Question 1: Proton pump inhibitors (PPIs) reduce gastric acid by:
- Blocking H2 receptors on parietal cells
- Irreversibly inhibiting H+/K+-ATPase on parietal cells (Correct answer)
- Neutralizing gastric acid chemically
- Stimulating somatostatin release
Correct answer: Irreversibly inhibiting H+/K+-ATPase on parietal cells
PPIs (e.g., omeprazole, pantoprazole) irreversibly inhibit the H+/K+-ATPase (proton pump) in gastric parietal cells, providing the most potent and sustained acid suppression.
Question 2: Which lipid-lowering drug class most effectively reduces LDL cholesterol and is first-line for ASCVD risk reduction?
- Fibrates
- Bile acid sequestrants
- Niacin
- Statins (HMG-CoA reductase inhibitors) (Correct answer)
Correct answer: Statins (HMG-CoA reductase inhibitors)
Statins inhibit HMG-CoA reductase, reducing hepatic cholesterol synthesis, upregulating LDL receptors, and producing the greatest LDL reduction with proven cardiovascular mortality benefit.
Question 3: Tamoxifen is used in the treatment of hormone receptor-positive breast cancer. Its mechanism of action is:
- Aromatase inhibition
- Selective estrogen receptor modulation (SERM) — blocks estrogen receptors in breast tissue (Correct answer)
- Progesterone receptor agonism
- HER2 receptor blockade
Correct answer: Selective estrogen receptor modulation (SERM) — blocks estrogen receptors in breast tissue
Tamoxifen is a SERM that competitively blocks estrogen receptors in breast tissue, preventing estrogen-driven tumor proliferation while acting as an estrogen agonist in bone and uterus.
Question 4: Which medication is the first-line treatment for C. difficile infection (CDI) of non-severe severity?
- Metronidazole (IV)
- Oral vancomycin or oral fidaxomicin (Correct answer)
- Oral metronidazole
- IV vancomycin
Correct answer: Oral vancomycin or oral fidaxomicin
Current IDSA/SHEA guidelines recommend oral vancomycin or fidaxomicin as first-line for non-severe CDI, replacing oral metronidazole which has inferior cure rates.
Question 5: When selecting an antibiotic for a UTI caused by MRSA, which agent is appropriate?
- Amoxicillin-clavulanate
- Trimethoprim-sulfamethoxazole (TMP-SMX) if susceptible, or nitrofurantoin (Correct answer)
- Ciprofloxacin
- Cephalexin
Correct answer: Trimethoprim-sulfamethoxazole (TMP-SMX) if susceptible, or nitrofurantoin
MRSA is resistant to beta-lactams; TMP-SMX or nitrofurantoin are appropriate for uncomplicated MRSA UTI if in vitro susceptibility is confirmed.
Question 6: Which class of antidepressant carries a black box warning for increased suicidality in patients under 24 years of age?
- Tricyclic antidepressants (TCAs) only
- MAO inhibitors only
- SNRIs only
- All antidepressants (Correct answer)
Correct answer: All antidepressants
The FDA requires a black box warning on ALL antidepressant classes for increased risk of suicidal thinking and behavior in children, adolescents, and young adults up to age 24.
Pharm.D. Doctor of Pharmacy Clinical Pharmacology and Therapeutics 2
Proton pump inhibitors (PPIs) reduce gastric acid by: