,NU 160 Exam 4 | Comprehensive Questions &
Verified Answers | 2026 Edition | Galen College
1. Which of the following best describes the mechanism of action of bethanechol?
A) Direct cholinergic agonist that stimulates muscarinic receptors
B) Indirect cholinergic agonist that inhibits acetylcholinesterase
C) Muscarinic antagonist that blocks acetylcholine
D) Nicotinic agonist that enhances skeletal muscle contraction
Correct Answer: Direct cholinergic agonist that stimulates muscarinic receptors
Rationale: Bethanechol binds directly to muscarinic cholinergic receptors, increasing bladder
and gastrointestinal smooth muscle tone. It is used for nonobstructive urinary retention. It does
not inhibit acetylcholinesterase, block muscarinic receptors, or act primarily on nicotinic
receptors.
2. The nurse is caring for a patient receiving atropine preoperatively. The nurse explains that
atropine is given to
A) increase gastric motility before surgery
B) reduce oral and respiratory secretions and prevent bradycardia
C) induce sedation and amnesia
D) reverse opioid overdose
Correct Answer: Reduce oral and respiratory secretions and prevent bradycardia
Rationale: Atropine blocks muscarinic receptors, decreasing salivary and bronchial secretions
and preventing vagally mediated bradycardia during intubation. It does not increase motility,
provide sedation, or reverse opioids.
,3. The nurse is teaching a patient about timolol eye drops for glaucoma. The patient should be
instructed to
A) apply the drops only when experiencing pain
B) increase fluid intake to prevent dry eyes
C) apply gentle pressure to the inner canthus after instillation to reduce systemic absorption
D) use the drops in both eyes even if glaucoma is unilateral
Correct Answer: Apply gentle pressure to the inner canthus after instillation to reduce systemic
absorption
Rationale: Timolol is a beta-blocker; punctal occlusion minimizes systemic absorption, reducing
the risk of bradycardia and bronchospasm. It is used daily, not as needed, and is prescribed for
the affected eye only.
4. The nurse is monitoring a patient receiving succinylcholine during rapid sequence intubation.
Which adverse effect is most concerning?
A) Hypertension
B) Tachycardia
C) Bronchospasm
D) Malignant hyperthermia and hyperkalemia
Correct Answer: Malignant hyperthermia and hyperkalemia
Rationale: Succinylcholine is a depolarizing neuromuscular blocker that can trigger malignant
hyperthermia and life-threatening hyperkalemia, especially in patients with burns, trauma, or
neuromuscular disease. Cardiovascular effects are variable.
5. Which of the following best describes the action of flumazenil?
A) Benzodiazepine receptor antagonist used to reverse sedation and respiratory depression
, B) Opioid antagonist
C) Neuromuscular blocker antagonist
D) Anticholinergic
Correct Answer: Benzodiazepine receptor antagonist used to reverse sedation and respiratory
depression
Rationale: Flumazenil competitively inhibits benzodiazepine binding at the GABA-A receptor,
reversing CNS depression. It does not reverse opioids, neuromuscular block, or cholinergic
effects. Seizures may occur in benzodiazepine-dependent patients.
6. The nurse is teaching a patient about the use of dextromethorphan for cough. The patient
should be instructed that
A) it is an expectorant that thins mucus
B) it suppresses the cough reflex in the medulla and should not be used with MAOIs
C) it is a bronchodilator
D) it causes significant drowsiness at recommended doses
Correct Answer: It suppresses the cough reflex in the medulla and should not be used with
MAOIs
Rationale: Dextromethorphan is a centrally acting antitussive; combining it with MAOIs can
cause serotonin syndrome. It is not an expectorant or bronchodilator and causes minimal
sedation at therapeutic doses.
7. The nurse is caring for a patient receiving pyridostigmine for myasthenia gravis. The nurse
should monitor for signs of cholinergic crisis, including
A) dry mouth and tachycardia
B) hypertension and pupil dilation
C) excessive salivation, muscle fasciculations, and diarrhea
Verified Answers | 2026 Edition | Galen College
1. Which of the following best describes the mechanism of action of bethanechol?
A) Direct cholinergic agonist that stimulates muscarinic receptors
B) Indirect cholinergic agonist that inhibits acetylcholinesterase
C) Muscarinic antagonist that blocks acetylcholine
D) Nicotinic agonist that enhances skeletal muscle contraction
Correct Answer: Direct cholinergic agonist that stimulates muscarinic receptors
Rationale: Bethanechol binds directly to muscarinic cholinergic receptors, increasing bladder
and gastrointestinal smooth muscle tone. It is used for nonobstructive urinary retention. It does
not inhibit acetylcholinesterase, block muscarinic receptors, or act primarily on nicotinic
receptors.
2. The nurse is caring for a patient receiving atropine preoperatively. The nurse explains that
atropine is given to
A) increase gastric motility before surgery
B) reduce oral and respiratory secretions and prevent bradycardia
C) induce sedation and amnesia
D) reverse opioid overdose
Correct Answer: Reduce oral and respiratory secretions and prevent bradycardia
Rationale: Atropine blocks muscarinic receptors, decreasing salivary and bronchial secretions
and preventing vagally mediated bradycardia during intubation. It does not increase motility,
provide sedation, or reverse opioids.
,3. The nurse is teaching a patient about timolol eye drops for glaucoma. The patient should be
instructed to
A) apply the drops only when experiencing pain
B) increase fluid intake to prevent dry eyes
C) apply gentle pressure to the inner canthus after instillation to reduce systemic absorption
D) use the drops in both eyes even if glaucoma is unilateral
Correct Answer: Apply gentle pressure to the inner canthus after instillation to reduce systemic
absorption
Rationale: Timolol is a beta-blocker; punctal occlusion minimizes systemic absorption, reducing
the risk of bradycardia and bronchospasm. It is used daily, not as needed, and is prescribed for
the affected eye only.
4. The nurse is monitoring a patient receiving succinylcholine during rapid sequence intubation.
Which adverse effect is most concerning?
A) Hypertension
B) Tachycardia
C) Bronchospasm
D) Malignant hyperthermia and hyperkalemia
Correct Answer: Malignant hyperthermia and hyperkalemia
Rationale: Succinylcholine is a depolarizing neuromuscular blocker that can trigger malignant
hyperthermia and life-threatening hyperkalemia, especially in patients with burns, trauma, or
neuromuscular disease. Cardiovascular effects are variable.
5. Which of the following best describes the action of flumazenil?
A) Benzodiazepine receptor antagonist used to reverse sedation and respiratory depression
, B) Opioid antagonist
C) Neuromuscular blocker antagonist
D) Anticholinergic
Correct Answer: Benzodiazepine receptor antagonist used to reverse sedation and respiratory
depression
Rationale: Flumazenil competitively inhibits benzodiazepine binding at the GABA-A receptor,
reversing CNS depression. It does not reverse opioids, neuromuscular block, or cholinergic
effects. Seizures may occur in benzodiazepine-dependent patients.
6. The nurse is teaching a patient about the use of dextromethorphan for cough. The patient
should be instructed that
A) it is an expectorant that thins mucus
B) it suppresses the cough reflex in the medulla and should not be used with MAOIs
C) it is a bronchodilator
D) it causes significant drowsiness at recommended doses
Correct Answer: It suppresses the cough reflex in the medulla and should not be used with
MAOIs
Rationale: Dextromethorphan is a centrally acting antitussive; combining it with MAOIs can
cause serotonin syndrome. It is not an expectorant or bronchodilator and causes minimal
sedation at therapeutic doses.
7. The nurse is caring for a patient receiving pyridostigmine for myasthenia gravis. The nurse
should monitor for signs of cholinergic crisis, including
A) dry mouth and tachycardia
B) hypertension and pupil dilation
C) excessive salivation, muscle fasciculations, and diarrhea
