MEDSCI303 | MEDSCI303 Pharmacy Exam 3
Version 3 | Questions with Correct Answers and
Expert Explanation for Each Question | Rajiv
Gandhi University of Health Sciences
1. A 68-year-old patient with severe COPD and a history of Heart Failure with Reduced
Ejection Fraction (HFrEF) requires a beta-blocker. Which agent is most appropriate to
minimize the risk of bronchospasm while providing mortality benefits?
A. Propranolol
B. Bisoprolol
C. Nadolol
D. Timolol
Correct Answer: B
Expert Explanation: Bisoprolol is a highly selective beta-1 adrenergic antagonist,
which reduces the risk of antagonizing beta-2 receptors in the lungs. In patients
with concurrent COPD and HFrEF, selective beta-blockers are preferred over non-
selective agents like Propranolol. Non-selective agents can induce significant
bronchoconstriction by blocking the bronchodilatory effects of endogenous
catecholamines. Clinical studies show that cardioselective beta-blockers provide
essential survival benefits in heart failure without worsening respiratory symptoms.
,Close monitoring of pulmonary function remains necessary whenever any beta-
blocker is initiated in respiratory patients.
2. A patient taking Theophylline for chronic asthma is prescribed Ciprofloxacin for a
urinary tract infection. What is the most likely pharmacological outcome of this
combination?
A. Increased theophylline levels due to CYP1A2 inhibition
B. Decreased theophylline levels due to enzyme induction
C. Reduced antibiotic efficacy due to gastric pH changes
D. Enhanced bronchodilation with no change in serum levels
Correct Answer: A
Expert Explanation: Ciprofloxacin is a potent inhibitor of the cytochrome P450
enzyme CYP1A2, which is the primary pathway for theophylline metabolism.
Inhibition of this enzyme leads to a significant reduction in theophylline clearance
and a subsequent rise in serum concentrations. Elevated theophylline levels can
lead to severe toxicity, including cardiac arrhythmias and seizures. The narrow
therapeutic index of theophylline necessitates frequent serum monitoring when
interacting drugs are introduced. Clinicians should consider alternative antibiotics
or proactively reduce the theophylline dose by approximately 30-50 percent.
,3. When initiating Sacubitril/Valsartan (Entresto) in a patient currently taking
Lisinopril for hypertension, what is the mandatory washout period required to prevent
angioedema?
A. 36 hours
B. 24 hours
C. 12 hours
D. 72 hours
Correct Answer: A
Expert Explanation: Sacubitril is a neprilysin inhibitor that prevents the
breakdown of bradykinin, a potent vasodilator. Since ACE inhibitors like Lisinopril
also increase bradykinin levels, combining them significantly increases the risk of
life-threatening angioedema. A strict 36-hour washout period is required when
switching from an ACE inhibitor to Sacubitril/Valsartan. This delay ensures that the
ACE enzyme activity recovers sufficiently before the neprilysin inhibitor is
introduced. This safety protocol is a critical component of clinical decision-making
in heart failure management.
4. A patient with atrial fibrillation is managed with Digoxin and Albuterol for asthma.
Which electrolyte abnormality increases the risk of Digoxin toxicity in this patient?
A. Hypernatremia
, B. Hypocalcemia
C. Hypokalemia
D. Hypermagnesemia
Correct Answer: C
Expert Explanation: Albuterol is a beta-2 agonist that can cause potassium to shift
from the extracellular space into the cells, leading to hypokalemia. Digoxin binds to
the same site as potassium on the Na+/K+-ATPase pump; therefore, low potassium
levels allow more Digoxin to bind. This increased binding enhances the drug’s
inhibitory effect, potentially leading to toxic manifestations even at normal serum
concentrations. Monitoring serum potassium is vital in patients using high doses of
rescue inhalers or nebulizers. Correcting electrolyte imbalances is the first step in
managing suspected Digoxin-related arrhythmias.
5. Which of the following medication classes is known to cause a dry cough that may
be misdiagnosed as an exacerbation of underlying asthma or COPD?
A. Calcium Channel Blockers
B. ACE Inhibitors
C. Thiazide Diuretics
D. HMG-CoA Reductase Inhibitors
Version 3 | Questions with Correct Answers and
Expert Explanation for Each Question | Rajiv
Gandhi University of Health Sciences
1. A 68-year-old patient with severe COPD and a history of Heart Failure with Reduced
Ejection Fraction (HFrEF) requires a beta-blocker. Which agent is most appropriate to
minimize the risk of bronchospasm while providing mortality benefits?
A. Propranolol
B. Bisoprolol
C. Nadolol
D. Timolol
Correct Answer: B
Expert Explanation: Bisoprolol is a highly selective beta-1 adrenergic antagonist,
which reduces the risk of antagonizing beta-2 receptors in the lungs. In patients
with concurrent COPD and HFrEF, selective beta-blockers are preferred over non-
selective agents like Propranolol. Non-selective agents can induce significant
bronchoconstriction by blocking the bronchodilatory effects of endogenous
catecholamines. Clinical studies show that cardioselective beta-blockers provide
essential survival benefits in heart failure without worsening respiratory symptoms.
,Close monitoring of pulmonary function remains necessary whenever any beta-
blocker is initiated in respiratory patients.
2. A patient taking Theophylline for chronic asthma is prescribed Ciprofloxacin for a
urinary tract infection. What is the most likely pharmacological outcome of this
combination?
A. Increased theophylline levels due to CYP1A2 inhibition
B. Decreased theophylline levels due to enzyme induction
C. Reduced antibiotic efficacy due to gastric pH changes
D. Enhanced bronchodilation with no change in serum levels
Correct Answer: A
Expert Explanation: Ciprofloxacin is a potent inhibitor of the cytochrome P450
enzyme CYP1A2, which is the primary pathway for theophylline metabolism.
Inhibition of this enzyme leads to a significant reduction in theophylline clearance
and a subsequent rise in serum concentrations. Elevated theophylline levels can
lead to severe toxicity, including cardiac arrhythmias and seizures. The narrow
therapeutic index of theophylline necessitates frequent serum monitoring when
interacting drugs are introduced. Clinicians should consider alternative antibiotics
or proactively reduce the theophylline dose by approximately 30-50 percent.
,3. When initiating Sacubitril/Valsartan (Entresto) in a patient currently taking
Lisinopril for hypertension, what is the mandatory washout period required to prevent
angioedema?
A. 36 hours
B. 24 hours
C. 12 hours
D. 72 hours
Correct Answer: A
Expert Explanation: Sacubitril is a neprilysin inhibitor that prevents the
breakdown of bradykinin, a potent vasodilator. Since ACE inhibitors like Lisinopril
also increase bradykinin levels, combining them significantly increases the risk of
life-threatening angioedema. A strict 36-hour washout period is required when
switching from an ACE inhibitor to Sacubitril/Valsartan. This delay ensures that the
ACE enzyme activity recovers sufficiently before the neprilysin inhibitor is
introduced. This safety protocol is a critical component of clinical decision-making
in heart failure management.
4. A patient with atrial fibrillation is managed with Digoxin and Albuterol for asthma.
Which electrolyte abnormality increases the risk of Digoxin toxicity in this patient?
A. Hypernatremia
, B. Hypocalcemia
C. Hypokalemia
D. Hypermagnesemia
Correct Answer: C
Expert Explanation: Albuterol is a beta-2 agonist that can cause potassium to shift
from the extracellular space into the cells, leading to hypokalemia. Digoxin binds to
the same site as potassium on the Na+/K+-ATPase pump; therefore, low potassium
levels allow more Digoxin to bind. This increased binding enhances the drug’s
inhibitory effect, potentially leading to toxic manifestations even at normal serum
concentrations. Monitoring serum potassium is vital in patients using high doses of
rescue inhalers or nebulizers. Correcting electrolyte imbalances is the first step in
managing suspected Digoxin-related arrhythmias.
5. Which of the following medication classes is known to cause a dry cough that may
be misdiagnosed as an exacerbation of underlying asthma or COPD?
A. Calcium Channel Blockers
B. ACE Inhibitors
C. Thiazide Diuretics
D. HMG-CoA Reductase Inhibitors
