BIO301 | BIO301 Pharmacology Exam 2 Version 1 |
Questions with Correct Answers and Expert
Explanation for Each Question | Saint Paul’s School
of Nursing
1. A patient is prescribed Bethanechol for postoperative urinary retention. Which of
the following is a primary contraindication for this medication?
A. Mechanical intestinal obstruction
B. Glaucoma
C. Hypothyroidism
D. Tachycardia
Correct Answer: A
Expert Explanation: Bethanechol is a direct-acting cholinergic agonist that
stimulates the detrusor muscle and relaxes the urinary sphincter. It is strictly
contraindicated in patients with mechanical bowel or urinary tract obstructions due
to the risk of organ rupture. The medication increases peristalsis and pressure
within the lumens of the gastrointestinal and urinary systems. Nurses must confirm
the absence of an anatomical blockage before administration to ensure patient
safety. Other contraindications include asthma and peptic ulcer disease due to
increased secretions and bronchoconstriction.
,2. What is the primary mechanism of action for Atropine when used to treat
symptomatic bradycardia?
A. Stimulation of Beta-1 adrenergic receptors
B. Blockade of muscarinic cholinergic receptors
C. Activation of the parasympathetic nervous system
D. Inhibition of acetylcholinesterase
Correct Answer: B
Expert Explanation: Atropine is a potent anticholinergic drug that works by
competitively blocking muscarinic receptors in the heart. By blocking the effects of
the vagus nerve, it effectively increases the heart rate and improves conduction
through the AV node. This action directly opposes the parasympathetic nervous
system’s inhibitory effects on the cardiac cycle. It is the first-line medication in the
ACLS protocol for managing acute bradyarrhythmias. Nurses must monitor for
secondary effects such as dry mouth and urinary retention following administration.
3. A patient is receiving Epinephrine via intravenous infusion for anaphylactic shock.
Which physiological response should the nurse anticipate?
A. Increased peripheral vascular resistance
B. Bronchoconstriction
C. Decreased cardiac output
,D. Miosis of the pupils
Correct Answer: A
Expert Explanation: Epinephrine is a non-selective adrenergic agonist that
stimulates Alpha-1, Beta-1, and Beta-2 receptors. Stimulation of Alpha-1 receptors
results in profound vasoconstriction, which increases peripheral vascular resistance
and blood pressure. Simultaneously, Beta-2 stimulation leads to bronchodilation,
which is critical during an anaphylactic reaction. Beta-1 activation increases heart
rate and contractility to support systemic perfusion. Monitoring the patient’s blood
pressure and cardiac rhythm is essential during an epinephrine infusion.
4. Which side effect is most closely associated with the use of Alpha-1 blockers like
Prazosin?
A. Hypertension
B. Orthostatic hypotension
C. Urinary retention
D. Bradycardia
Correct Answer: B
Expert Explanation: Prazosin is an Alpha-1 adrenergic antagonist used primarily
for the treatment of hypertension and benign prostatic hyperplasia. By blocking
Alpha-1 receptors on vascular smooth muscle, it causes vasodilation and lowers
, blood pressure. A significant adverse effect is the ‘first-dose phenomenon,’ which
presents as profound orthostatic hypotension. Patients should be instructed to
change positions slowly and take the initial dose at bedtime to prevent falls. Reflex
tachycardia may also occur as the body attempts to compensate for the drop in
blood pressure.
5. A patient with asthma is diagnosed with hypertension. Which medication should
the nurse question if it is prescribed for this patient?
A. Metoprolol
B. Lisinopril
C. Atenolol
D. Propranolol
Correct Answer: D
Expert Explanation: Propranolol is a non-selective beta-blocker that inhibits both
Beta-1 and Beta-2 adrenergic receptors. Blocking Beta-2 receptors in the lungs can
lead to bronchospasm, which is life-threatening for patients with asthma or COPD.
Cardioselective beta-blockers like Metoprolol or Atenolol are generally preferred in
respiratory patients as they primarily target Beta-1 receptors in the heart. The
nurse must assess the patient’s respiratory history before administering any non-
Questions with Correct Answers and Expert
Explanation for Each Question | Saint Paul’s School
of Nursing
1. A patient is prescribed Bethanechol for postoperative urinary retention. Which of
the following is a primary contraindication for this medication?
A. Mechanical intestinal obstruction
B. Glaucoma
C. Hypothyroidism
D. Tachycardia
Correct Answer: A
Expert Explanation: Bethanechol is a direct-acting cholinergic agonist that
stimulates the detrusor muscle and relaxes the urinary sphincter. It is strictly
contraindicated in patients with mechanical bowel or urinary tract obstructions due
to the risk of organ rupture. The medication increases peristalsis and pressure
within the lumens of the gastrointestinal and urinary systems. Nurses must confirm
the absence of an anatomical blockage before administration to ensure patient
safety. Other contraindications include asthma and peptic ulcer disease due to
increased secretions and bronchoconstriction.
,2. What is the primary mechanism of action for Atropine when used to treat
symptomatic bradycardia?
A. Stimulation of Beta-1 adrenergic receptors
B. Blockade of muscarinic cholinergic receptors
C. Activation of the parasympathetic nervous system
D. Inhibition of acetylcholinesterase
Correct Answer: B
Expert Explanation: Atropine is a potent anticholinergic drug that works by
competitively blocking muscarinic receptors in the heart. By blocking the effects of
the vagus nerve, it effectively increases the heart rate and improves conduction
through the AV node. This action directly opposes the parasympathetic nervous
system’s inhibitory effects on the cardiac cycle. It is the first-line medication in the
ACLS protocol for managing acute bradyarrhythmias. Nurses must monitor for
secondary effects such as dry mouth and urinary retention following administration.
3. A patient is receiving Epinephrine via intravenous infusion for anaphylactic shock.
Which physiological response should the nurse anticipate?
A. Increased peripheral vascular resistance
B. Bronchoconstriction
C. Decreased cardiac output
,D. Miosis of the pupils
Correct Answer: A
Expert Explanation: Epinephrine is a non-selective adrenergic agonist that
stimulates Alpha-1, Beta-1, and Beta-2 receptors. Stimulation of Alpha-1 receptors
results in profound vasoconstriction, which increases peripheral vascular resistance
and blood pressure. Simultaneously, Beta-2 stimulation leads to bronchodilation,
which is critical during an anaphylactic reaction. Beta-1 activation increases heart
rate and contractility to support systemic perfusion. Monitoring the patient’s blood
pressure and cardiac rhythm is essential during an epinephrine infusion.
4. Which side effect is most closely associated with the use of Alpha-1 blockers like
Prazosin?
A. Hypertension
B. Orthostatic hypotension
C. Urinary retention
D. Bradycardia
Correct Answer: B
Expert Explanation: Prazosin is an Alpha-1 adrenergic antagonist used primarily
for the treatment of hypertension and benign prostatic hyperplasia. By blocking
Alpha-1 receptors on vascular smooth muscle, it causes vasodilation and lowers
, blood pressure. A significant adverse effect is the ‘first-dose phenomenon,’ which
presents as profound orthostatic hypotension. Patients should be instructed to
change positions slowly and take the initial dose at bedtime to prevent falls. Reflex
tachycardia may also occur as the body attempts to compensate for the drop in
blood pressure.
5. A patient with asthma is diagnosed with hypertension. Which medication should
the nurse question if it is prescribed for this patient?
A. Metoprolol
B. Lisinopril
C. Atenolol
D. Propranolol
Correct Answer: D
Expert Explanation: Propranolol is a non-selective beta-blocker that inhibits both
Beta-1 and Beta-2 adrenergic receptors. Blocking Beta-2 receptors in the lungs can
lead to bronchospasm, which is life-threatening for patients with asthma or COPD.
Cardioselective beta-blockers like Metoprolol or Atenolol are generally preferred in
respiratory patients as they primarily target Beta-1 receptors in the heart. The
nurse must assess the patient’s respiratory history before administering any non-
