Donepezil is an acetylcholinesterase (AChE) inhibitor. Which of the following is consistent with the action of this drug?
The drug cannot cross the blood–brain barrier.
The drug must be taken 30 minutes before meals.
The drug is used to treat mild and severe forms of Alzheimer's disease.
✓
The drug requires twice-daily dosing due to a short half-life.
Correct Answer
The drug is used to treat mild and severe forms of Alzheimer's disease.
The drug will cross the blood–brain barrier, has a 70-hour half-life, and is unaffected by oral intake.
Question 2
In Alzheimer's disease, which pharmacologic action within the brain will reduce the symptoms seen with this progressive disease?
Decreased action of acetylcholinesterase (AChE)
✓
Inhibition of the release of acetylcholine (ACh) from presynaptic neurons
Decreased sensitivity of cholinergic receptors on the postsynaptic neuron
Increased amount of available acetylcholinesterase (AChE)
Correct Answer
Decreased action of acetylcholinesterase (AChE)
Because a decreased level of ACh is present in this disease, decreasing the action of AChE can help reduce the symptoms because less ACh will be broken down.
Question 3
A nurse is teaching a 74-year-old client how to properly apply a rivastigmine transdermal patch. Which of the following statements from the client requires additional teaching?
"I should apply the patch over a clean, hairless, and intact area of the skin."
"Sites should be rotated and the same site should not be used for 14 days."
"The patch needs to be changed weekly."
✓
"The old patch must be removed before a new patch is put on."
Correct Answer
"The patch needs to be changed weekly."
The patch needs to be changed every 24 hours, not weekly. All the other options are correct statements.
Question 4
The client asks the nurse how the drug memantine works in the body. What is the nurse's best response to the client's question?
"The drug binds directly to the cholinergic receptors and blocks calcium from entering the cell."
"It inhibits the cholinesterase enzyme so that less ACh will be broken down into choline and acetone."
"It will bind directly to the centrally acting muscarinic receptors to enhance cognitive function."
"The drug binds to the magnesium site on the glutamate receptor to slow calcium influx into the cell."
✓
Correct Answer
"The drug binds to the magnesium site on the glutamate receptor to slow calcium influx into the cell."
Memantine is an NMDA receptor antagonist. When too much calcium enters the cell, it makes it extremely excitable, interfering with cognition. Too much calcium is toxic. Normally, glutamate binds to the NMDA receptors for a brief period, allowing the calcium channel to open. Glutamate then dissociates from the receptors and magnesium binds to the NMDA receptors, closing the calcium channel and preventing further calcium from entering.
Question 5
A client taking donepezil has been prescribed a new drug. Which drug prescription should the nurse question?
Acetaminophen
Propranolol
✓
Second-generation H1RAs
Selective serotonin reuptake inhibitors (SSRIs)
Correct Answer
Propranolol
Propranolol is a nonselective beta blocker; therefore, one would be concerned about extremely low heart rate plus bronchoconstriction.
Question 6
Which AChE inhibitor should be stopped immediately if the client notices a rash?
Pyridostigmine
Galantamine
✓
Neostigmine
Donepezil
Correct Answer
Galantamine
There is a potential for serious and life-threatening skin rashes when using this drug. Stevens–Johnson syndrome, a disorder of the skin and mucous membranes characterized by a painful rash that disseminates, is one example. Blisters form, and eventually the top skin layer will die and shed.
Question 7
A client has just been diagnosed with mild Alzheimer's disease. The health care provider prescribes donepezil oral disintegrating tablet 5 mg daily. What key point should the client be taught about how to take this drug?
"The drug is soft enough that you can chew it if you are afraid of choking."
"You may crush the pill and mix with food if you have problems swallowing the whole pill."
"This medication should only be taken in the morning with your breakfast."
"Allow the drug to completely dissolve on your tongue. Do not swallow it whole."
✓
Correct Answer
"Allow the drug to completely dissolve on your tongue. Do not swallow it whole."
The drug was prescribed as a disintegrating tablet, so it must completely dissolve on the tongue. It is not to be chewed, crushed, or swallowed whole.
Question 8
What indicates an optimal dosage of acetylcholinesterase (AChE) inhibitors for clients with myasthenia gravis?
Increased ability to raise eyelids
✓
Pupil constriction
Increased intestinal motility
Muscle relaxation
Correct Answer
Increased ability to raise eyelids
The AChE inhibitors prescribed for myasthenia gravis increase muscle strength and muscle relaxation. Since clients may have drooping of the eyes due to muscle weakness, the ability to raise the eyelids independently is evident of increased muscle strength.
Question 9
The nurse is assigned to a client with a diagnosis of myasthenia gravis. The client was taking pyridostigmine 1000 mg daily. Due to the exacerbation of their symptoms, the provider increased the dose to 1500 mg daily. What condition should the nurse be assessing?
Sinus tachycardia
Fluid volume deficit
✓
Fluid volume overload
Hypertension
Correct Answer
Fluid volume deficit
Because the client's dose was increased, they are at risk for cholinergic crisis. This is characterized by increased urine output, diarrhea, vomiting, excess salivation, and diaphoresis.
Question 10
The nurse should be prepared to administer which drug to a client experiencing a cholinergic drug overdose?
Atropine
✓
Propranolol
Pilocarpine
Epinephrine
Correct Answer
Atropine
If there is cholinergic toxicity, an anticholinergic should be given to counteract the signs and symptoms. For instance, atropine will increase the heart rate and decrease intestinal motility and inhibit contraction of the detrusor muscle.