Unit 5: Chapter 32 (Karch 7th Ed) - Cholinergic Agonists Flashcards
1. The patient has had cevimeline (Evoxac) prescribed. What would be an appropriate dosing schedule for the nurse to administer this drug? A) Once a day B) Twice a day C) Three times a day D) Every 4 hours
Ans: C
Feedback:
Cevimeline should be given three times a day with meals. Once or twice a day dosing would cause a
decrease in therapeutic effects of the drug and every 4 hours could lead to toxicity.
- A student asks the pharmacology instructor to describe the function of a cholinergic agonist. What
would the instructor reply?
A) Cholinergic agonists increase the activity of dopamine receptor sites throughout the brain and
spinal cord.
B) Cholinergic agonists decrease the activity of gamma-aminobutyric acid (GABA) receptor sites
throughout the body.
C) Cholinergic agonists increase the activity of acetylcholine receptor sites throughout the body.
D) Cholinergic agonists decrease the activity of norepinephrine receptor sites throughout the brain and
spinal cord.
Ans: C
Feedback:
Cholinergic agonists are drugs that increase the activity of acetylcholine receptor sites throughout the
body. Dopamine, GABA, and norepinephrine are not associated with cholinergic agonist function.
- A 10-year-old child with spina bifida is receiving bethanechol (Urecholine) for treatment of neurogenic
bladder. What adverse effect will the nurse assess for?
A) Constipation
B) Loss of bowel and bladder control
C) Decrease salivation
D) Increased appetite
Ans: B
Feedback:
Loss of bowel and bladder control is an adverse effect of cholinergic agents that would cause stress in a
child. Diarrhea and increased salivation are also adverse effects. Increased appetite is not associated
with these drugs. Children are more likely to have gastrointestinal (GI) upset that could result in a
decrease in appetite.
4. A nurse is writing a plan of care for a patient who is taking bethanechol (Urecholine). What would be an appropriate outcome for this patient? A) Pupillary dilation B) Increased blood pressure C) Improved bladder function D) Decreased secretions
Ans: C
Feedback:
Bethanechol is prescribed for nonobstructive urinary retention and neurogenic bladder. The appropriate
outcome for this patient would be improved bladder function. This drug causes pupillary constriction
and increased secretions. This drug would not increase blood pressure. However, it could cause
hypotension in the older patient.
5. What drug is the nurse likely to administer to diagnose myasthenia gravis in a child? A) Atropine (generic) B) Bethanechol (Urecholine) C) Edrophonium (Enlon, Reversol) D) Neostigmine (Prostigmine)
Ans: C
Feedback:
Edrophonium is the drug of choice for diagnosing myasthenia gravis. Bethanechol is used to treat
neurogenic bladder. Neostigmine is used for treatment of myasthenia gravis and could be used for
diagnosis if edrophonium could not be used. Atropine is an anticholinergic drug and would not be used
to test for myasthenia gravis
- A patient is brought to the emergency department having a cholinergic reaction, which includes a
severe drop in blood pressure. What drug will the nurse expect to administer?
A) Atropine (generic)
B) Edrophonium (Enlon, Reversol)
C) Propranolol (Inderal)
D) Succinylcholine (Anectine)
Ans: A
Feedback:
The antidote for a cholinergic reaction is atropine. This drug will block the cholinergic sites.
Edrophonium would cause an accumulation of acetylcholine and worsen the situation. Propranolol
blocks beta-receptors in the sympathetic system. Succinylcholine is a neuromuscular junction drug and
would not affect other sites.
- Memantine hydrochloride (Namenda) has been prescribed for a 63-year-old patient who has a
confirmed diagnosis of Alzheimer’s disease. What would be the target dose for this patient?
A) 5 mg/d
B) 10 mg b.i.d.
C) 15 mg/d
D) 20 mg b.i.d.
Ans: B
Feedback:
The drug is started at 5 mg/d PO, increasing by 5 mg/d at weekly intervals. The target dose is 20 mg/d
given as 10 mg b.i.d.
- An Alzheimer’s patient taking donepezil (Aricept) has a complete blood count that indicates he or she
is anemic. What drug taken in combination with donepezil could be the cause of the anemia?
A) Cimetidine (Tagamet)
B) Ibuprofen (Advil)
C) Diltiazem (Cardizem)
D) Furosemide (Lasix)
Ans: B
Feedback:
There could be an increased risk of gastrointestinal (GI) bleeding if donepezil is taken with a
nonsteroidal anti-inflammatory drug (NSAID) because of the combination of increased GI secretions
and the GI mucosal erosion associated with the use of NSAIDs. Cimetidine, diltiazem, and furosemide
would not affect GI bleeding.
9. The Air Force nurse is treating a patient who was exposed to a particular nerve gas. What drug has been approved to treat this patient? A) Neostigmine (Prostigmin) B) Pyridostigmine (Mestinon) C) Ambenonium (Mytelase) D) Edrophonium (Enlon, Reversol)
Ans: B
Feedback:
Pyridostigmine has been approved for use by military personnel who have been exposed to particular
nerve gases. Neostigmine, ambenonium, and edrophonium are not approved for this use.
- The nurse administers a direct-acting cholinergic agonist to the patient. When assessing this patient for
drug effects, the nurse would expect to see effects arising from stimulation of what receptors?
A) Nicotinic
B) Alpha
C) Beta
D) Muscarinic
Ans: D
Feedback:
The direct-acting cholinergic agonists are similar to acetylcholine (ACh) and react directly with
receptor sites to cause the same reaction as if Ach had stimulated the receptor sites. These drugs usually
stimulate muscarinic receptors within the parasympathetic system. They are used as systemic agents to
increase bladder tone, urinary excretion, and gastrointestinal (GI) secretions. One drug is used as an
ophthalmic agent to induce miosis to relieve the increased intraocular pressure of glaucoma. They have
no effect on alpha and beta receptors in the sympathetic nervous system and little impact on nicotinic
- The nurse is caring for a 49-year-old patient, who has been receiving bethanechol (Duvoid) for 1 week.
The patient develops progressive muscle weakness and respiratory difficulty. Edrophonium is ordered
and injected and the patient’s symptoms worsen. How would the nurse interpret this response?
A) Myasthenic crisis
B) Cholinergic crisis
C) Anaphylactic reaction
D) Pulmonary edema
Ans: B
Feedback:
The patient with a cholinergic crisis presents with progressive muscle weakness and respiratory
difficulty because the accumulation of acetylcholine at the cholinergic receptor site leads to reduced
impulse transmission and muscle weakness. This is a crisis when the respiratory muscles are involved.
Myasthenic crisis and cholinergic crisis display similar clinical pictures. The drug edrophonium can be
used as a diagnostic agent to distinguish the two conditions. If the patient improves immediately after
the edrophonium injection, the problem is a myasthenic crisis, which is improved by administration of
the cholinergic drug. If the patient gets worse, the problem is probably a cholinergic crisis, so
withdrawal of the patient’s cholinergic drug along with intense medical support is indicated. The
situation does not depict an anaphylactic reaction or pulmonary edema.
- A 70-year-old female patient has just been diagnosed with Alzheimer’s disease. What cholinergic drug
is used for the treatment of Alzheimer’s disease?
A) Bethanechol (Duvoid)
B) Neostigmine (Prostigmin)
C) Donepezil (Aricept)
D) Edrophonium (Enlon, Reversol)
Ans: C
Feedback:
Currently, there are four reversible indirect-acting cholinergic agonists available to slow the
progression of this disease. These include tacrine (Cognex), galantamine (Razadyne), rivastigmine
(Exelon), and donepezil (Aricept). Edrophonium (Enlon, Reversol) is used to diagnose myasthenia
gravis; neostigmine is used for the diagnosis and management of myasthenia gravis; and bethanechol is
used to treat neurogenic bladder.
- The 38-year-old patient has just been administered edrophonium (Enlon, Reversol). The nurse will
know whether this patient has myasthenia gravis if the patient exhibits what within 30 minutes after
receiving the medication?
A) Increased muscle strength
B) Decreased adventitious breath sounds
C) Decreased muscle spasms
D) Increased urinary output
Ans: A
Feedback:
Edrophonium is administered to diagnose myasthenia gravis because administration of this drug will
cause a marked increase in muscle strength within 30 minutes of administration if the patient has this
disease. Edrophonium does not produce decreased adventitious breath sounds, decreased muscle
spasms, or increased urinary output.
14. When the nurse administers a cholinergic agonist to the patient, the nurse’s expectation is that what system will be stimulated? A) Sympathetic nervous system B) Parasympathetic nervous system C) Central nervous system D) Voluntary nervous system
Ans: B
Feedback:
Cholinergic agonists act at the same site as the neurotransmitter acetylcholine (ACh) and increase the
activity of the ACh receptor sites throughout the body. Because these sites are found extensively
throughout the parasympathetic nervous system, their stimulation produces a response similar to what
is seen when the parasympathetic system is activated. These drugs do not stimulate the sympathetic,
central, or voluntary nervous systems.
- A 78-year-old patient is admitted to the emergency department and is diagnosed with bradycardia. The
patient tells the nurse he or she is taking donepezil (Aricept), a cholinergic agent, for Alzheimer’s
disease. The nurse will anticipate what drug will be ordered to treat the patient’s bradycardia?
A) Atropine
B) Pseudoephedrine
C) Propranolol
D) Bethanechol
Ans: A
Feedback:
Maintain a cholinergic blocking drug on standby, such as atropine, to use as an antidote for excessive
doses of cholinergic drugs to reverse overdose or counteract severe reactions arising from use of
cholinergic agonists. Atropine will block cholinergic effects that are causing this patient’s heart rate to
decline. Bethanechol will slow the heart rate further whereas propranolol and pseudoephedrine will not
reverse the cholinergic stimulation