Pharmacology - Prep U - Chapter 31

Which are classified as sympatholytic drugs? (Select all that apply.)

Beta-adrenergic blockers Alpha-adrenergic blockers Alpha- and beta-adrenergic blockers are classified as sympatholytic drugs.

A patient is receiving sotalol. Which instruction would be most important for the nurse to provide to the patient to ensure maximum effectiveness of the drug?

"Be sure to take the drug on an empty stomach." Sotalol absorption is decreased by the presence of food; to ensure maximum effectiveness of the drug, the patient should take it on an empty stomach, not with an antacid or after a large meal. The dose is typically divided during the day and should not be taken all at once.

A male client diagnosed with bone cancer has an order for clonidine on his chart. The nurse is concerned that this may be a mistake and asks another nurse why clonidine would be ordered for this client. What would be an appropriate response from the second nurse?

"Clonidine is sometimes prescribed for severe pain in cancer clients like this client." Clonidine is prescribed to treat severe pain in clients with cancer. Clonidine does not have an effect on cancer cells. A nurse should not blindly follow orders. Clonidine is given for hypertension, not hypotension.

A male client has been prescribed an alpha1-selective adrenergic blocking agent to treat benign prostatic hyperplasia (BPH) 2 weeks ago. Which assessment question should the nurse ask to evaluate for the expected result of this medication therapy?

"Has your urine stream improved since beginning the medication?" Alpha1-selective adrenergic blocking agents are used to treat hypertension and are often used to treat BPH because of their relaxing effects on the bladder and prostate. Reporting a better urine stream would indicate the medication therapy has achieved its therapeutic goal. None of the other options assess an expected outcome for alpha1-selective adrenergic blocking medication therapy.

The male client is prescribed prazosin (Minipress) for hypertension. He asks the nurse how the medication works. What is the nurse's best response?

"It works by making your blood vessels dilate." Prazosin (Minipress) is a peripherally acting antiadrenergic drug that causes the blood vessels to expand. Calcium channel blockers inhibit the movement of calcium across the membrane and increase the supply of oxygen to the heart.

A 75-year-old male client was admitted to the unit with angina. The client was started on nadolol (Corgard). The client asks why this medication was prescribed since the client does not have high blood pressure. What is the nurse's best response?

"Some beta blockers are approved as anti-anginal agents." Decreased heart rate, contractility, and excitability, as well as a membrane-stabilizing effect, lead to a decrease in arrhythmias, a decreased cardiac workload, and decreased oxygen consumption. The juxtaglomerular cells are not stimulated to release renin, which further decreases the blood pressure. These effects are useful in treating hypertension and chronic angina and can help to prevent reinfarction after an MI by decreasing cardiac workload and oxygen consumption. Corgard will not prevent blood pressure problems in the future or prevent you from developing glaucoma. Corgard is not used to treat BPH.

A patient is to receive metoprolol. What would the nurse include in the teaching plan for this patient?

"Take this drug with food to help promote its absorption." Food increases the bioavailability of the drug and facilitates its absorption. Metoprolol crosses the blood-brain barrier leading to a possible increase in CNS adverse effects. Metoprolol, like other beta-1 selective blockers, can lead to decreased exercise tolerance. Metoprolol, like other beta-1 selective blockers, can lead to decreased libido and impotence.

A female client has been diagnosed with hyperthyroidism. She asks the nurse why she is taking a medication that decreases her blood pressure like her grandmother takes. What is the nurse's best response when teaching her about the action and use of propranolol (Inderal) in the treatment of hyperthyroidism?

"The administration of propranolol will decrease your heart rate." The administration of propranolol (Inderal) to a client who has been diagnosed with hyperthyroidism will allow for decreased heart rate. It is not administered to promote bronchodilation, prevent respiratory depression, or decrease systolic blood pressure.

A client has been prescribed labetalol. What assessment evaluates the effectiveness of the medication?

A decrease from baseline blood pressure. Labetalol is an adrenergic blocking agent prescribed to lower blood pressure. Monitor patient response to the drug by documenting improvement (lowering) in blood pressure. Cardiac arrhythmias and orthostatic hypotension are side effectives of the medication. Abrupt withdrawal of the medication can induce an MI with the associated chest pain.

A nurse is caring for a patient who has been administered a centrally acting anti-adrenergic drug. The nurse knows that under which condition is the use of a centrally acting anti-adrenergic drug contraindicated?

Active hepatic disease The use of a centrally acting anti-adrenergic drug is contraindicated in patients with active hepatic disease. The use of a centrally acting anti-adrenergic drug is not contraindicated in patients with active peptic ulcer, ulcerative colitis, or mental depression. In patients with active peptic ulcer, ulcerative colitis, or mental depression, the use of peripherally acting anti-adrenergic drug is contraindicated.

First-dose effect occurs when the client experiences marked hypotension and syncope with sudden loss of consciousness with the first few doses of the sympatholytic. Which intervention might be helpful for the nurse to do to decrease the risk for first-dose effect?

Administer the dose at bedtime The nurse can administer the dose at bedtime to decrease the risk of first-dose effect. The nurse should never administer half the prescribed dose, or at longer intervals than prescribed, any modifications must be ordered by the health care provider. Administering any drugs with food must be approved as food can delay absorption and may be contraindicated.

Propranolol (Inderal) is used extensively as treatment for what condition?

Angina The beta-adrenergic blocking agents are used to treat cardiovascular problems (hypertension, angina, migraine headaches) and to prevent reinfarction after MI. These drugs are widely used today and include: carteolol (Cartrol), nadolol (Corgard), nebivolol (Bystolic), penbutolol (Levator), pindolol (Visken), propranolol (Inderal), sotalol (Betapace, Betapace AF), and timolol (Blocadren, Timoptic). The prototype drug, propranolol, was in fact the most prescribed drug in the country in the 1980s. Propranolol does not prevent first MIs and it is not used for hypotension or cluster headaches.

A patient has a history of smoking. Which agent would the nurse most likely expect to be ordered?

Atenolol Atenolol is a beta-1 selective adrenergic blocker. This agent would be preferred for the patient who smokes because the drug does not usually block beta-1 receptor sites. Subsequently, it does not block the sympathetic bronchodilation that would be important for this patient. Timolol, pindolol, and nadolol are nonselective beta-adrenergic blockers that would block this sympathetic bronchodilation.

The nurse knows that which class of drugs prevents epinephrine and norepinephrine from occupying receptor sites on the cell membranes?

Beta-adrenergic blocking drugs Beta-adrenergic blocking drugs prevent epinephrine and norepinephrine from occupying receptor sites on cell membranes. Beta-adrenergic drugs stimulate epinephrine and norepinephrine release so that they can occupy more of the receptor sites. Beta Blocking agonist cause epinephrine to bind to sites causing airways to open. There is no such thing as beta-helping drugs.

A group of nursing students are reviewing information about adrenergic blockers. The students demonstrate understanding when they identify which as an example of an alpha/beta-adrenergic blocking drug?

Carvedilol Carvedilol is an example of an alpha/beta-adrenergic blocking drug. Metoprolol is a beta blocker. Prazosin is a peripherally acting antiadrenergic drug. Reserpine is a peripherally acting antiadrenergic drug.

A client calls the cardiology office and reports fatigue and drowsiness since starting a new medication. The nurse knows that which medications has these as common side effects?

Carvedilol Cavedilol is an alpha/beta adrenergic blocking drug often used to treat heart failure. Common side effects include fatigue, dizziness, hypotension, drowsiness, insomnia, weakness, diarrhea, dyspnea, chest pain, bradycardia, and skin rashes. Norepinephrine and epinephrine side effects include increased heart rate and jitteriness. Lisinopril often causes lightheadedness due to a decrease in blood pressure and a nonproductive cough. Fatigue is not a common side effect from norepinephrine, epinephrine, or lisinopril.

A client has come to get lab results at the cardiology clinic. The nurse notes that the digoxin level is elevated. The nurse knows that what other medication may be responsible for the increase in digoxin level?

Carvedilol When taking both carvedilol and digoxin, the client's digoxin level becomes higher and the client is at greater risk of digoxin toxicity. Prozac, Zantac, and ampicillin do not increase a client's digoxin level.

A client has been prescribed a beta blocker. The nurse knows that beta blockers can have which effect on the heart?

Decrease the heart rate Beta blockers decrease (not increase) heart rate and dilate blood vessels (not the heart itself). Beta blockers do not prevent normal sinus rhythm.

A client has been prescribed an adrenergic blocking drug for glaucoma. Which nursing interventions should the nurse include when teaching the client?

Demonstrate the technique of eye drop instillation The nurse should demonstrate the technique of eye drop installation while educating the client with glaucoma. Demonstrating the method of cleaning eyes, suggesting the client protect his eyes from exposure to sunlight, and informing the client about eye drop preservation are not related nursing interventions when teaching the client about the use of an adrenergic blocker for glaucoma.

Nonselective beta blockers are the drugs of choice for treating hypertension in patients who smoke.

False Beta-1-selective blockers, because they do not block the sympathetic bronchodilation, are the preferred drugs for treating hypertension in patients who smoke.

After reviewing information about nonselective adrenergic blockers, a group of students demonstrate a need for additional teaching when they identify what as an effect of these agents?

Increased pulse rate Nonselective adrenergic blockers block the effects of norepinephrine at the alpha and beta receptors in the sympathetic nervous system, leading to a slower pulse rate, lowering of blood pressure, increased renal perfusion, and decreased renin levels.

A client presents to the emergency department reporting rapid heart rate, severe headache, and pounding in the chest. While obtaining the clients history, the nurse learns the client stopped taking medications because the prescriptions ran out and had no funds to refill them. The nurse knows that which medications being abruptly stopped could be causing these symptoms?

Labetalol Abruptly stopping an adrenergic blocking drug can cause increased heart rate, hypertension, headache, and pounding in the chest. Antidepressants have a long half-life, so side effects when they are discontinued take longer to develop. Stopping Tylenol PM may cause pain to resurface and an inability to sleep but not usually hypertension, rapid heart beat, and pounding in the chest. Stopping Reglan abruptly does not normally cause any sudden symptoms.

A client has been prescribed labetalol IV for a pheochromocytoma. What is the expected effect of the medication?

Management of the resulting hypertension Labetalol is used IV and orally to treat hypertension associated with pheochromocytoma (tumor of the chromaffin cells of the adrenal medulla, which periodically releases large amounts of norepinephrine and epinephrine into the system) and clonidine withdrawal. Labetalol is not prescribed to affect tumor shrinkage. The tumor is responsible for the increase in norepinephrine not of urine.

A nurse is caring for a patient with arrhythmia. What nursing interventions should the nurse perform when a patient with life-threatening arrhythmia receives an adrenergic-blocking drug through IV?

Monitor blood pressure and respiratory rate The nurse should monitor blood pressure and respiratory rate when the patient with life-threatening arrhythmia receives an adrenergic-blocking drug through IV. The nurse need not monitor rhythm at varying intervals, pulse rate, and body temperature. The nurse monitors rhythm at varying intervals and pulse rate when propranolol is administered orally for less serious cardiac arrhythmia.

A patient is diagnosed with a pheochromocytoma. Which medications provide adjunctive therapy in the treatment of hypertension and tachycardia?

Nonselective alpha-blocking agents Nonselective alpha-blocking drugs are used as antihypertensive drugs only when hypertension is caused by excessive catecholamines. Excessive catecholamines may result from pheochromocytoma. Diuretic agents, alpha-adrenergic stimulant agents, and cardiotonic agents are not used as adjunctive agents for pheochromocytoma.

The student nurses are learning about drugs that act on the ANS. The students should learn that adrenergic blocking agents prevent which neurotransmitters from being released and causing SNS effects to be blocked?

Norepinephrine Adrenergic blocking agents prevent norepinephrine from being released from the adrenal medulla or from the nerve terminal from activating the receptor, which blocks SNS effects. Epinephrine, serotonin, and GABA are not associated with this process.

A client prescribed propranolol reports a history of asthma. What nursing intervention should the nurse implement immediately to best assure the client's safety?

Notify the health care provider of the contraindication between asthma and the effects of propranolol The nonselective adrenergic blocking agents are contraindicated in patients with asthma, which could be exacerbated by the loss of norepinephrine's effect of bronchodilation. None of the remaining options assures client safety as identifying the issue and alerting the health care provider so alternative treatment can be prescribed.

A client is suspected of having pheochromocytoma. Which agent would the nurse identify as being used to help diagnose this disorder?

Phentolamine Phenotolamine is the drug used to diagnose pheochromocytoma. Labetalol is used to treat the hypertension that is associated with pheochromocytoma. Carvedilol is used to treat hypertension, but not that associated with pheochromocytoma. Atenolol is used to treat myocardial infarction, chronic angina, and hypertension; it is not used to diagnose pheochromcytoma.

A nursing instructor determines that a class on adrenergic blockers was successful when the students identify which medications as an alpha-adrenergic blocker?

Phentolamine Phentolamine is an alpha-adrenergic blocker. Metoprolol is a beta-adrenergic blocker. Atenolol is a beta-adrenergic blocker. Clonidine is a centrally acting antiadrenergic drug.

A client has received a dose of dopamine intravenously. The client's IV was infiltrated, and the dopamine was injected into the subcutaneous tissues. Which medication will prevent the vasoconstriction and tissue necrosis based on this action?

Phentolamine mesylate (Regitine) Phentolamine mesylate (Regitine) can be used to prevent tissue necrosis due to extravasation of potent vasoconstrictors, such as norepinephrine and dopamine, into subcutaneous tissues.

A nurse is reviewing a client's history and medications prior to discharge. The client has been prescribed a new antiadrenergic medication. Which condition or medication would require the nurse to talk with the provider prior to discharge? Select all that apply.

Pregnancy Active hepatitis B Renal impairment Treatment for depression with an MAOI Contraindications for clients taking antiadrenergic drugs include active liver disease (hepatitis B), treatment with an MAOI, renal impairment, and pregnancy. Polycythemia is not a contraindication for treatment with an antiadrenergic medication.

The nurse is preparing a teaching plan for a patient who is to receive a nonselective beta blocker. The nurse would make sure to address safety measures as a priority for the patient receiving:

Propranolol Although safety measures are important part of the teaching plan for any nonselective beta blocker, they would be a priority for a patient receiving propranolol. The drug crosses the blood-brain barrier, leading to the development of CNS effects. Carteolol, nadolol, and sotalol do not cross the blood-brain barrier; thus, the risk for CNS effects would be less.

Beta-1 selective blockers have what as an effect?

Reduction in arrhythmia Beta-1 selective blockers decrease the release of renin to aid in decreasing blood pressure. Beta-1 selective blockers decrease heart rate. Beta-1 selective blockers decrease cardiac excitability and exert a membrane stabilizing effect leading to a decrease in arrhythmias. Beta-1 selective blockers decrease cardiac workload.

Which would a nurse identify as a contraindication for the use of a beta-1 selective blocker?

Sinus bradycardia Beta-1 selective blockers are contraindicated in patients with sinus bradycardia. Diabetes, thyroid disease, and chronic obstructive pulmonary disease are conditions that require cautious use of beta-1 selective blockers.

After teaching a group of students about beta-1 selective blockers, the instructor determines that the teaching was successful when the students identify what as a contraindication to using this group of drugs?

Sinus bradycardia Beta-1 selective blockers are contraindicated in patients with sinus bradycardia. Thyroid disease is a condition that requires cautious use of beta-1 selective blockers. Diabetes is a condition that requires cautious use of beta-1 selective blockers. COPD is a condition that requires cautious use of beta-1 selective blockers.

The nursing instructor is discussing adverse effects of non-selective alpha-adrenergic blocking drugs. What adverse effect would the nurse monitor for when giving a client phentolamine (Rogitine)?

Tachycardia Phentolamine blocks the postsynaptic alpha1-adrenergic receptors, decreasing sympathetic tone in the vasculature and causing vasodilation, which leads to a lowering of blood pressure. It also blocks presynaptic alpha2-receptors, preventing the feedback control of norepinephrine release. The result is an increase in reflex tachycardia that occurs when blood pressure is lowered. The nurse would not monitor this client for hypertension, wheezing, or depressed respirations as adverse effects of phentolamine.

A patient has been diagnosed with benign prostatic hypertrophy and has been prescribed prazosin (Minipress) to assist in the treatment of the symptoms. How does this alpha1-blocking agent decrease urinary retention?

The medication inhibits urinary bladder contraction. Prazosin (Minipress) can be administered in multiple doses to inhibit urinary bladder contraction to decrease urinary retention. The administration of prazosin (Minipress) is not used to increase gastric motility, increase muscle contraction, or decrease blood pressure when administered for benign prostatic hypertrophy.

A client has been prescribed the nonselective beta-adrenergic blocker, timolol for for the treatment of open angle glaucoma. What instructions should the nurse provide to assure the effectiveness of the medication?

The proper method for instilling eye drops Timolol is available in an ophthalmic form of the drug for reduction of intraocular pressure in patients with open-angle glaucoma. The client should in instructed in the proper method of instilling eye drops. None of the other options present information that is relevant to the administration of timolol for open angle glaucoma.

A patient with benign prostatic hypertrophy (BPH) has been prescribed tamsulosin. How do alpha1-adrenergic blocking agents, such as tamsulosin, assist in treating the symptoms of BPH?

They inhibit contraction of the urinary bladder. Alpha1-adrenergic blocking agents can prevent alpha-mediated contraction of smooth muscle in nonvascular tissue. This action makes these drugs useful in the treatment of BPH, which is characterized by obstructed urine flow as the enlarged prostate gland presses on the urethra. Alpha1-blocking agents can decrease urinary retention and improve urine flow by relaxing muscles in the prostate and urinary bladder.

The instructor is preparing a teaching plan for a group of students that describes nonselective beta adrenergic blockers. What would the instructor address? (Select all that apply.)

Timolol Pindolol Nebivolol Nebivolol is a nonselective beta blocker. Pindolol is a nonselective beta blocker. Timolol is a nonselective beta blocker. Atenolol is a beta-1 selective blocker. Betaxolol is a beta-1 selective blocker. Esmolol is a beta-1 selective blocker.

A patient is receiving tamsulosin. The nurse understands that this drug is most likely being given for which reason?

To relax prostatic smooth muscles Tamsulosin blocks smooth muscle receptors in the prostate, prostatic capsule, prostatic urethra, and urinary bladder neck, which leads to a relaxation of the bladder and prostate and improved flow of urine in males. A decrease in vascular tone would lead to a lowering of blood pressure; tamsulosin is not used to treat hypertension. Vasodilation would lead to a lowering of blood pressure; tamsulosin is not used to treat hypertension. Tamsulosin, an alpha-1 selective blocker, does not cause the reflex tachycardia that can occur with a drop in blood pressure; tamsulosin is not indicated for the treatment of hypertension.

A client has recently been prescribed a drug that treats hypertension by blocking the sympathetic receptors in the sympathetic nervous system. This action is characteristic of which?

an adrenergic antagonist. Those drugs that stimulate sympathetic receptors are referred to as adrenergic or dopaminergic agonists (stimulators), and those that block are referred to as adrenergic antagonists (blockers). Adrenergic antagonism is not synonymous with the action of a cardiotonic drug.

What is the first drug of choice for treatment of a client with a history of a myocardial infarction (MI) 2 years ago?

beta-blockers Class II beta-adrenergic blockers are being used more often in clients following myocardial infarction and heart failure because of their effectiveness in improving symptoms, reducing hospitalization, and improving survival. A calcium channel blocker blocks the entry of calcium into the muscle cells of the heart and the arteries. By reducing the heart's need for oxygen, CCBs prevent or relieve angina. CCBs also are used for treating high blood pressure because of their blood pressure-lowering effects. Clinical trials support the use of digoxin (a cardiac glycoside) in heart failure in clients with left ventricular dysfunction, especially in those with advanced disease. Angiotensin II receptor blockers (ARBs) lower blood pressure and help prevent a heart attack or stroke.

The nurse is assessing the client for adverse CNS effects after administering a nonselective adrenergic blocker based on the understanding that these effects occur due to:

blockage of norepinephrine's effect. CNS effects occur with nonselective adrenergic blockers because the effects of norepinephrine are blocked in the CNS. GI effects of a nonselective adrenergic blocker are related to parasympathetic dominance. Cardiovascular effects occur with nonselective adrenergic blockers because of the lack of stimulatory effects and loss of vascular tone in the cardiovascular system. Respiratory effects occur with nonselective adrenergic blockers because of the loss of bronchodilation and vasodilation of the mucous membrane vessels.

A patient is receiving a beta-1 selective blocker after a myocardial infarction to prevent reinfarction. The nurse understands that the rationale for using the drug would be to:

decrease cardiac workload. A beta-1 selective blocker is helpful after a myocardial infarction because it decreases the cardiac workload and myocardial oxygen demand. The drug decreases contractility, excitability, and the heart rate. Although it also decreases blood pressure, it is not this effect that makes it a useful in preventing reinfarction.

A nurse is caring for a client in the critical care unit. Phentolamine (Regitine, OraVerse) has been ordered for the management of tissue necrosis caused by extravasation of parenterally administered drugs. Before administering this drug, the nurse will check the client's chart for indications of:

history of acute myocardial infarction. The nurse will check the chart for any indication of a history of acute myocardial infarction. Phentolamine is contraindicated in clients with this history or any evidence of coronary artery disease because of its cardiac-stimulating effects and resultant increases in myocardial oxygen demand. This drug is used with caution in clients with gastric and duodenal ulcers because the drug has a histamine-like effect. Obesity and diabetes mellitus should not be a factor with the use of phentolamine.

A patient with diabetes who uses insulin is also receiving labetalol. The nurse would monitor the patient closely for:

hypoglycemia. Labetalol, a nonselective adrenergic blocker, increases the effectiveness of antidiabetic agents leading to an increased risk for hypoglycemia. Hypotension would occur if the drug were combined with other drugs that are known to lower blood pressure. Arrhythmias and bronchospasm are adverse effects of nonselective adrenergic blockers and are unrelated to the combination of labetalol and insulin.

Which observation might indicate that timolol is achieving the desired effect in a client?

intraocular pressure decreases Timolol is a beta blocker used for treatment of glaucoma and hypertension. Depending on the intended use, a decrease in the client's intraocular pressure or blood pressure is an indication that the drug is achieving the desired effect.

The nurse frequently sees mature male clients with BPH seeking treatment for symptoms. After ensuring they do not test positive for prostate cancer, pharmacological intervention is one of a few treatment modalities available. Pharmacokinetics indicate alpha1-blocking agents as a treatment choice due to their:

prevention of smooth muscle contraction in nonvascular tissues. Alpha1-adrenergic blocking drugs can prevent alpha-mediated contraction of smooth muscle in nonvascular tissues.

The nurse is providing medication education to a client prescribed an adrenergic blocker. Which nervous system is the specific focus of this classification of medications?

sympathetic Adrenergic blocking agents are also called sympatholytic drugs because they lyse, or block, the effects of the sympathetic nervous system.