Evolve - Chapter 20 (Cholinergic Drugs)

The nurse is caring for a patient with Alzheimer's disease. The primary health care provider has prescribed donepezil (Aricept). The patient asks, "How will this drug help me for Alzheimer's disease?" Which response made by the nurse would be accurate? 1. "It will reduce your anxiety." 2. "It will cure you from Alzheimer's disease." 3. "It will help you to remember things." 4. "It will help you to have proper sleep."

3. "It will help you to remember things." Rationale: Donepezil (Aricept) increases the levels of acetylcholine. It helps by increasing the patient's cognitive and functioning ability, thereby helping with memory. A patient diagnosed with Alzheimer's disease may be anxious about the condition, but donepezil (Aricept) does not have an anxiolytic effect. Donepezil (Aricept) does not cure Alzheimer's disease; in fact, there is no proper cure for this. Sleep is a side effect related to Donepezil (Aricept). However, the main purpose of prescribing this drug to the patient is not to enhance sleep.

Which medication should be administered to a patient who has a cholinergic crisis? 1. Atropine 2. Donepezil 3. Echothiophate 4. Pyridostigmine

1. Atropine Rationale: Overdose of a cholinergic drug causes a cholinergic crisis. Atropine is a cholinergic antagonist; therefore, it is administered to reverse the action of a cholinergic drug. Donepezil is used to treat Alzheimer's disease. Echothiophate is used to reduce intraocular pressure. Pyridostigmine is used as an antidote for neuromuscular blocker toxicity.

The patient with myasthenia gravis was initially prescribed pyridostigmine (Mestinon). After reviewing the medical history of the patient, the nurse informs the primary health care provider (PHP) that the patient has asthma. What instruction would the nurse receive from the PHP? 1. Discontinue administering pyridostigmine (Mestinon). 2. Teach deep breathing exercises to the patient. 3. Elevate the patient's bed while sleeping. 4. Administer pyridostigmine (Mestinon) intramuscularly.

1. Discontinue administering pyridostigmine (Mestinon). Rationale: Cholinergic drugs such as pyridostigmine (Mestinon) should not be administered to the patient with asthma because it will worsen the symptoms. Pyridostigmine (Mestinon) may cause muscle cramps and difficulty in breathing. Therefore, it should be discontinued in asthma patients. Deep breathing exercises and elevating the patient's bed may not help to prevent the adverse effects caused by pyridostigmine (Mestinon). Administering pyridostigmine (Mestinon) worsens the symptoms of asthma, and the patient will face breathing difficulty. Therefore, the nurse should avoid administering pyridostigmine (Mestinon) intramuscularly.

A geriatric patient with Alzheimer's disease is admitted to the hospital due to overdose of rivastigmine (Exelon). Following the assessment, the primary health care provider (PHP) instructs the nurse to administer epinephrine (Twinject). Based on which findings does the PHP give such instruction? 1. The patient had difficulty in breathing. 2. The patient had dilated pupils. 3. The patient had dryness of mouth. 4. The patient had fluid retention.

1. The patient had difficulty in breathing. Rationale: Rivastigmine (Exelon) is a cholinergic drug used for the treatment of Alzheimer's disease. It improves cognition by increasing the levels of acetylcholine. Overdosage of cholinergic drugs may lead to bronchoconstriction and difficulty in breathing. An epinephrine agonist such as epinephrine (Twinject) alleviates bronchoconstriction and cardiovascular disorders. Cholinergic drugs such as rivastigmine (Exelon) cause constriction of the pupils, excessive salivation, and fluid loss. Hence, dilated pupils, dryness of the mouth, and fluid retention will not be observed in the patient. Epinephrine (Twinject) does not reverse these symptoms.

The nurse advises a patient who is taking cholinergic drugs to avoid standing immediately and to take an upright position slowly. Which complication associated with the drug is the nurse trying to prevent? 1. Muscle cramps 2. Postural hypotension 3. Nausea and vomiting 4. Dyspnea

2. Postural hypotension Rationale: The main adverse effect of cholinergic drugs in the patient is postural hypotension, which results in dizziness and fainting. This effect can be decreased by changing positions slowly when taking an upright position. These drugs do not affect muscular function, gastrointestinal function, or respiratory function. Therefore, muscle cramps, nausea or vomiting, and dyspnea are not adverse effects related to cholinergic drugs.

Which condition is treated with bethanechol (Urecholine) in a postoperative patient? 1. Postoperative hypotension 2. Urinary atony 3. Respiratory atelectasis 4. Postoperative ischemic colitis

2. Urinary atony Rationale: Bethanechol is a direct-acting cholinergic agonist that stimulates the cholinergic receptors on the smooth muscle of the bladder, leading to bladder contraction and emptying, leading to urinary atony. Postoperative hypotension is the contraindication to cholinergic drugs. Antihistamines are used to treat respiratory atelectasis in postoperative patients.

A patient who had undergone surgery reports atony of the bladder. Which cholinergic drug does the nurse expect to be prescribed to the patient? 1. Donepezil (Aricept) 2. Cevimeline (Evoxac) 3. Bethanechol (Urecholine) 4. Succinylcholine (Anectine)

3. Bethanechol (Urecholine) Rationale: Bethanechol (Urecholine) is a direct-acting cholinergic drug that is used to treat atony of the bladder. It is the only direct-acting cholinergic drug that is administered orally. Donepezil (Aricept), cevimeline (Evoxac), and succinylcholine (Anectine) are not useful for treating atony of the bladder. Donepezil (Aricept) is an indirect-acting cholinergic drug that is used to treat Alzheimer's disease. Cevimeline (Evoxac) is a direct-acting cholinergic drug used in the treatment of xerostomia (dry mouth) due to Sjögren's syndrome. Succinylcholine (Anectine) is used in general anesthesia as a neuromuscular blocker.

Which assessment most assists the nurse in determining if bethanechol (Urecholine) has had a therapeutic effect? 1. Neurologic assessment 2. Muscular assessment 3. Urinary assessment 4. Gastric assessment

3. Urinary assessment Rationale: Bethanechol (Urecholine) increases the tone of the detrusor muscle and causes the patient to void. Because it is used to initiate voiding, the nurse does not need to complete a neurological, muscular, or gastric assessment to determine effectiveness.

What is a clinical indicator of parasympathetic nervous system stimulation? 1. Dilation of the pupils 2. Retention of urine 3. Dilation of the bronchi 4. Slowing of the heart rate

4. Slowing of the heart rate Rationale: The parasympathetic nervous system performs seven regulatory functions: slowing the heart rate, increasing gastric secretions, emptying the bladder, emptying the bowel, focusing the eye for near vision, constricting the pupil, and contracting bronchial smooth muscle. Alpha stimulation leads to dilation of pupil. Parasympathetic nervous system stimulation helps in relaxation of the bladder, allowing emptying of the bowels. Cholinergic drugs help the bronchi to contract rather than dilate.

The nurse is assessing a patient who is on cholinergic drug therapy. The nurse finds that the patient has abdominal cramps and hypotension and is at risk of cardiac arrest. According to the nurse, what is the possible reason for the patient's condition? 1. The patient had an allergic reaction. 2. The patient had a drug interaction. 3. The patient had consumed alcohol. 4. The patient had an overdose of the drug.

4. The patient had an overdose of the drug. Rationale: Cholinergic drugs mimic the effects of acetylcholine by binding to cholinergic receptors. An overdose of cholinergic drugs acts directly on the parasympathetic nervous system and activates the nicotinic receptors. An overdose of the drug shows its adverse effect in increased gastrointestinal secretions, which cause abdominal cramps. This drug reduces the heart rate considerably, thereby leading to hypotension. This may also cause atrioventricular block, leading to cardiac arrest. An allergic reaction to the drug causes dry mouth, sedation, and constipation but not abdominal cramps and hypotension. The patient has no history of co-administering medications; therefore a drug interaction is not likely. Alcohol does not interact with cholinergic drugs.