Unit 5 Pharm Chapter 32 Flashcards
The nurse has administered a 10-year-old client’s scheduled dose of bethanechol. What follow-up assessment should the nurse prioritize?
A) Cognitive assessment
B) Gastrointestinal assessment
C) Assessment of urine output
D) Assessment for dry mouth
C) Assessment of urine output
Rationale:Bethanechol is approved for the treatment of neurogenic bladder in children older than 8 years of age. A child taking this drug should have his or her urine output monitored closely. This would be a priority over dry mouth. The client’s cognition and GI function would not normally be affected.
A client receiving neostigmine uses naproxen for relief of low back pain. The nurse would caution the client to report what?
A) Blurred vision
B) Blood in stool
C) Muscle weakness
D) Increased bruising
B) Blood in stool
Rationale:The combination of naproxen, a nonsteroidal antiinflammatory agent, with neostigmine increases the client’s risk for GI bleeding, which would be manifested by blood in the stool or emesis. Increased bruising, muscle weakness, and blurred vision are not associated with the combined use of neostigmine and naproxen.
What statement best describes the action of direct-acting cholinergic agonists?
A) They undergo a chemical reaction with acetylcholinesterase.
B) They occupy receptor sites for acetylcholine.
C) They mimic the action of the sympathetic nervous system.
D) They prevent the breakdown of acetylcholine
B) They occupy receptor sites for acetylcholine.
Rationale:Direct-acting cholinergic agonists occupy receptor sites for acetylcholine on the membranes of effector cells. Indirect-acting cholinergic agonists react chemically with acetylcholinesterase to prevent it from breaking down acetylcholine. Indirect-acting cholinergic agonists react chemically with acetylcholinesterase to prevent it from breaking down acetylcholine. Cholinergic agonists in general are often called parasympathomimetic because their action mimics that of the parasympathetic nervous system.
What adverse effects might a nurse assess in a client receiving bethanechol? Select all that apply.
A) Dehydration
B) Tachycardia
C) Diaphoresis
D) Pallor
E) Diarrhea
A) Dehydration
C) Diaphoresis
E) Diarrhea
Rationale:Diarrhea is a possible adverse effect of bethanechol. Dehydration is possible due to the adverse effect of diarrhea. Increased sweating is a possible adverse effect of bethanechol. Bradycardia would occur with bethanechol. Flushing is a possible adverse effect of bethanechol.
What is the duration of action the nurse would expect following administration of bethanechol?
A) 1 to 6 hours
B) 30 to 60 minutes
C) 2 to 4 hours
D) 6 to 8 hours
A) 1 to 6 hours
Rationale:The duration of action for bethanechol is 1 to 6 hours with an onset in 30 to 90 minutes and a peak effect in 60 to 90 minutes.
The pregnant woman with myasthenia gravis has been taken off all indirect-acting cholinergic agents normally taken to treat her condition. The woman asks the nurse, “What would happen if I took my medicine for myasthenia gravis anyway?” What is the nurse’s best explanation of why the drug is contraindicated during pregnancy?
A) “Taking your indirect-acting cholinergic agent could cause overstimulation of your heart.”
B) “Taking indirect-acting cholinergic agents while pregnant could result in a uterine rupture.”
C) “Taking your indirect-acting cholinergic agent could cause birth defects.”
D) “Taking your indirect-acting cholinergic agent could stimulate labor.”
D) “Taking your indirect-acting cholinergic agent could stimulate labor.”
Rationale:Anticholinesterase inhibitors are contraindicated in pregnancy because the uterus could be stimulated and labor induced. The other statements are not factually true
The nurse, transcribing an order for a direct-acting cholinergic agent, would consider what condition to be a contraindication to its use? Select all that apply.
A) Bladder obstruction
B) Peptic ulcer disease
C) Asthma
D) Pregnancy
E) Bradycardia
A) Bladder obstruction
B) Peptic ulcer disease
C) Asthma
E) Bradycardia
Rationale:Contraindications for the use of direct-acting cholinergic agents include bradycardia, peptic ulcer disease, bladder obstruction, and asthma. Direct-acting cholinergic agents are used cautiously during pregnancy.
When administering a direct-acting cholinergic agonist to the older adult, what assessment should the nurse prioritize?
A) Serum potassium level
B) Serum blood sugar
C) Respiratory function
D) Blood pressure
D) Blood pressure
Rationale:The older client should be started on lower doses of the drugs and should be monitored very closely for potentially serious arrhythmias or hypotension, so blood pressure and pulse assessment are of particular importance. The drug is not associated with alterations in serum blood sugar, respiratory function, or potassium levels.
Why are indirect-acting cholinergic agonists used for treatment of myasthenia gravis but direct-acting agents are ineffective?
A) Indirect-acting cholinergic agents can cross the blood–brain barrier.
B) Indirect-acting cholinergic agents reduce production of acetylcholinesterase.
C) Direct-acting cholinergic agents have very short durations of action.
D) Direct-acting cholinergic agents allow acetylcholine to accumulate.
D) Direct-acting cholinergic agents allow acetylcholine to accumulate.
Rationale:Accumulation of acetylcholine leads to increased and prolonged stimulation of receptor sites, and this factor makes them effective in treating myasthenia gravis. However, direct-acting cholinergic agonists directly stimulate receptors, making them inefficient at treating the disease. Indirect-acting cholinergic agents do not reduce production of acetylcholinesterase, and the fact that they can cross the blood–brain barrier does not explain why they are used to treat myasthenia gravis. Direct-acting cholinergic agents have varied durations of action that are not shorter than those of the indirect-acting cholinergic agents.
The nurse is assessing a client who has been taking direct-acting cholinergic agonists. What assessment finding should the nurse attribute to this medication?
A) Blood pressure 121/68 mm Hg
B) Drowsiness
C) Three bowel movements over the past 4 days
D) Heart rate 62 beats/min
D) Heart rate 62 beats/min
Rationale:Direct-acting cholinergic agonists can cause bradycardia, hypotension, diarrhea, and urinary urgency. This client’s blood pressure is well within reference ranges, and his or her bowel pattern is typical. Drowsiness does not result from cholinergics.
The nurse is caring for a client with myasthenia gravis. What medication is the nurse most likely to administer?
A) Rivastigmine
B) Tacrine
C) Neostigmine
D) Galantamine
C) Neostigmine
Rationale:Neostigmine is used to treat myasthenia gravis. Galantamine, rivastigmine, and tacrine are used to treat Alzheimer disease.
Which of the indirect-acting cholinergic agonists has the shortest duration of action?
A) Neostigmine
B) Pyridostigmine
C) Namzaric
D) Edrophonium
D) Edrophonium
Rationale:Edrophonium is administered intravenously and has a very short duration of action (10 to 20 minutes). Neostigmine has a 2- to 4-hour duration of action. Pyridostigmine has a longer duration of action than neostigmine (3 to 6 hours). Namzaric is an extended release capsule combining memantine and donepezil.
When reviewing cholinergic agonists, the nurse learns that there are direct-acting and indirect-acting cholinergic agonists. What is it the agent acts directly or indirectly on?
A) Nerve impulse transmission
B) Acetylcholine receptor sites
C) Acetylcholine production
D) Acetylcholine potency
B) Acetylcholine receptor sites
Rationale:The direct-acting cholinergic agonists are similar to ACh and react directly with receptor sites to cause the same reaction as if ACh had stimulated the receptor sites. The indirect-acting cholinergic agonists block acetylcholinesterase, leading to increased ACh in the synapse.
What effects are associated with the use of cholinergic agonists?
A) Pupil dilation
B) Increased heart rate
C) Increased gastric motility
D) Increased contractility of the heart
C) Increased gastric motility
Rationale:Cholinergic agonists increase gastric motility, constrict pupils, decrease heart rate, decrease heart contractility, decrease cardiac conduction, increase gastric secretions, and relax sphincters.
A client with progressive muscle weakness is undergoing diagnostic testing for myasthenia gravis. Neostigmine 0.022 mg/kg has been prescribed, and the client weighs 144.8 lbs. How much neostigmine should the nurse administer? Provide your answer to two decimal places.
_____________mg
1.45mg
Rationale:The client’s weight must first be converted to kilograms by dividing it by 2.2. 144.8 ÷ 2.2 = 65.82 kg. The prescribed dose is 0.022 mg/kg, and 65.82 × 0.022 = 1.448 mg. To two decimal places, this is rounded to 1.45 mg.
