Exam 1 Study Questions

Which corticosteroid is most appropriate to administer to a woman in preterm labor to accelerate fetal lung maturation? A. Betamethasone B. Fludrocortisone C. Hydrocortisone D. Prednisone

Correct answer = A. A corticosteroid with high glucocorticoid activity is needed to speed fetal lung maturation prior to delivery. Betamethasone has high glucocorticoid activity and is one of the recommended drugs in this context. Dexamethasone is the other. Fludrocortisone mainly has mineralocorticoid activity and is not useful in this situation. Hydrocortisone has much lower glucocorticoid activity. Prednisone has a higher glucocorticoid activity than hydrocortisone, but the fetus is not able to convert it to prednisolone, the active form.

Which is correct regarding activation of receptors on the effector organs in the ANS? A. Acetylcholine activates muscarinic receptors. B. Acetylcholine activates adrenergic receptors. C. Epinephrine activates nicotinic receptors. D. Norepinephrine activates muscarinic receptors.

Correct answer = A. Acetylcholine is the neurotransmitter in the cholinergic system, and it activates both muscarinic and nicotinic cholinergic receptors, not adrenergic receptors. Norepinephrine and epinephrine activate adrenergic receptors, not muscarinic receptors.

Botulinum toxin blocks the release of acetylcholine from cholinergic nerve terminals. Which is a possible effect of botulinum toxin? A. Skeletal muscle paralysis B. Improvement of myasthenia gravis symptoms C. Increased salivation D. Reduced heart rate

Correct answer = A. Acetylcholine released by cholinergic neurons acts on nicotinic receptors in the skeletal muscle cells to cause contraction. Therefore, blockade of ACh release causes skeletal muscle paralysis. Myasthenia gravis is an autoimmune disease where antibodies are produced against nicotinic receptors and inactivate nicotinic receptors. A reduction in ACh release therefore worsens (not improves) the symptoms of this condition. Reduction in ACh release by botulinum toxin causes reduction in secretions including saliva (not increase in salivation), causing dry mouth and an increase (not reduction) in heart rate due to reduced vagal activity.

Which physiological change is expected when the sympathetic system is inhibited using a pharmacological agent? A. Reduction in heart rate B. Increase in blood pressure C. Decrease in fluid secretions D. Constriction of blood vessels

Correct answer = A. Activation of the sympathetic system causes an increase in heart rate, increase in blood pressure, reduction or thickening of fluid secretions, and constriction of blood vessels. Therefore, inhibition of the sympathetic system should theoretically cause a reduction in heart rate, decrease in blood pressure, increase in fluid secretions, and relaxation of blood vessels.

A 22-year-old male is brought to the emergency room with suspected cocaine overdose. Which of the following symptoms is most likely in this patient? A. Hypertension B. Bronchoconstriction C. Bradycardia D. Miosis (constriction of pupil)

Correct answer = A. Cocaine is an indirect adrenergic agonist that prevents the reuptake of norepinephrine into the nerve terminals, thus increasing the levels of NE in the synaptic cleft. The increase in NE leads to an increase in blood pressure (hypertension), tachycardia (not bradycardia), mydriasis (not miosis), and other symptoms of sympathetic overactivity.

Which adverse effect commonly occurs with glucocorticoid therapy? A. Glaucoma B. Hyperkalemia C. Weight loss D. Osteoarthritis

Correct answer = A. Glucocorticoid therapy may cause hypokalemia, not hyperkalemia. Glucocorticoids also cause increased appetite and osteoporosis. Glaucoma is a known potential adverse effect of this class.

Which of the following is correct regarding β-blockers? A. Treatment with β-blockers should not be stopped abruptly. B. Propranolol is a cardioselective β-blocker. C. Cardioselective β-blockers worsen asthma. D. β-Blockers decrease peripheral resistance by causing vasorelaxation.

Correct answer = A. If β-blocker therapy is stopped abruptly, that could cause angina and rebound hypertension. This could be due to the up-regulation of β receptors in the body. β-Blockers do not cause direct vasorelaxation. Therefore, they do not decrease peripheral resistance with short-term use. Propranolol is a nonselective β-blocker (not cardioselective). Cardioselective β-blockers antagonize only β 1 receptors and do not worsen asthma, as they do not antagonize β 2 receptors.

Which is correct regarding neurotransmitters and neurotransmission? A. Neurotransmitters are released from the presynaptic nerve terminals. B. Arrival of an action potential in the postsynaptic cell triggers release of neurotransmitter. C. Intracellular calcium levels drop in the neuron before the release of neurotransmitter. D. Serotonin and dopamine are the primary neurotransmitters in the ANS.

Correct answer = A. Neurotransmitters are released from presynaptic neurons, triggered by the arrival of an action potential in the presynaptic neuron (not in the postsynaptic cell). When an action potential arrives in the presynaptic neuron, calcium enters the presynaptic neuron and calcium levels increase in the neuron before neurotransmitter is released. The main neurotransmitters in the ANS are norepinephrine and acetylcholine.

Which is correct regarding membrane receptors and signal transduction? A. ANS neurotransmitters bind to membrane receptors on the effector cells, which leads to intracellular events. B. Cholinergic muscarinic receptors are ionotropic receptors. C. Cholinergic nicotinic receptors are metabotropic receptors. D. Metabotropic receptors activate ion channels directly.

Correct answer = A. Neurotransmitters generally bind to membrane receptors on the postsynaptic effector cells and cause cellular effects. Acetylcholine (ACh) binds to cholinergic muscarinic receptors and activates the second messenger pathway in effector cells, which in turn causes cellular events. Receptors that are coupled to second messenger systems are known as metabotropic receptors. Metabotropic receptors do not directly activate ion channels. ACh also binds to cholinergic nicotinic receptors and activates ion channels on the effector cells. The receptors that directly activate ion channels are known as ionotropic receptors.

Which of the following is correct regarding adrenergic neurotransmission? A. Norepinephrine is the major neurotransmitter released from sympathetic nerve terminals. B. Norepinephrine is mainly released from the adrenal glands. C. Tricyclic antidepressants and cocaine prevent the release of norepinephrine from the nerve terminals. D. Monoamine oxidase (MAO) converts dopamine to norepinephrine in the nerve terminal.

Correct answer = A. Norepinephrine (NE) is the major neurotransmitter released from sympathetic nerve terminals. Epinephrine, not norepinephrine, is mainly released from the adrenal glands. Tricyclic antidepressants (TCAs) and cocaine inhibit the reuptake of norepinephrine into the sympathetic nerve terminals, but they do not prevent the release of NE. Dopamine is converted to norepinephrine by dopamine β-hydroxylase, not by MAO.

An ICU patient with severe lung injury requires a neuromuscular blocking agent to assist in his ventilator management. He has liver disease and is currently in renal failure. Which neuromuscular blocker is the best choice for this patient? A. Cisatracurium B. Pancuronium C. Vecuronium D. Rocuronium

Correct answer = A. Pancuronium is renally eliminated and the patient has renal failure. Vecuronium and rocuronium are hepatically metabolized and the patient has liver disease. Cisatracurium is cleared by organ-independent metabolism (Hofmann elimination).

Which is correct regarding ganglion-blocking drugs? A. Blockade of sympathetic ganglia could result in reduced blood pressure. B. Blockade of parasympathetic ganglia could result in reduced heart rate. C. Nicotine is a nondepolarizing ganglion blocker. D. Atropine is a nondepolarizing ganglion blocker.

Correct answer = A. Selective blockade (in theory) of the sympathetic ganglion causes reduction in norepinephrine release and, therefore, reduction in heart rate and blood pressure. Selective blockade (in theory) of the parasympathetic ganglion causes reduction in ACh release and an increase in heart rate. Receptors at both sympathetic and parasympathetic ganglia are of the nicotinic type. Nicotine is an agonist at nicotinic receptors and produces a depolarizing block in the ganglia. Atropine is a muscarinic antagonist and has no effect on the nicotinic receptors found in the ganglia.

Which drug is useful in treating sinus bradycardia? A. Atropine B. Cisatracurium C. Neostigmine D. Succinylcholine

Correct answer = A. Sinus bradycardia is a condition where the heart rate is below normal and most often caused by increased vagal tone (increased release of ACh in the sinoatrial [SA] node that acts on muscarinic receptors to reduce heart rate). A muscarinic antagonist such as atropine is useful in this situation to bring the heart rate back to normal. Succinylcholine and cisatracurium are nicotinic antagonists and have no effect on muscarinic receptors in the SA node. Neostigmine is a cholinesterase inhibitor and can worsen bradycardia by increasing the level of ACh in the SA node.

Which contributes to osteoporosis with long-term use of glucocorticoids? A. Increased excretion of calcium B. Inhibition of calcium absorption C. Stimulation of the hypothalamic-pituitary-adrenal axis D. Decreased production of prostaglandins

Correct answer = B. Glucocorticoid-induced osteoporosis is attributed to inhibition of calcium absorption and bone formation. Increased intake of calcium plus vitamin D and use of bisphosphonates may be indicated. Glucocorticoids suppress rather than stimulate the hypothalamic-pituitary-adrenal axis. The decreased production of prostaglandins does not play a role in bone formation.

Which of the following is correct regarding responses mediated by adrenergic receptors? A. Stimulation of α1 receptors increases blood pressure. B. Stimulation of sympathetic presynaptic α2 receptors increases norepinephrine release. C. Stimulation of β2 receptors increases heart rate (tachycardia). D. Stimulation of β2 receptors causes bronchoconstriction.

Correct answer = A. Stimulation of α 1 receptors, mostly found in the blood vessels, causes vasoconstriction and an increase in blood pressure. Stimulation of α 2 receptors on the sympathetic presynaptic terminal reduces the release of norepinephrine. β 2receptors are not found in the heart, so activation of β 2receptors does not affect heart rate. Stimulation of β 2 receptors found in the bronchial tissues causes bronchodilation, not bronchoconstriction.

An elderly female who lives in a farmhouse was brought to the emergency room in serious condition after ingesting a liquid from an unlabeled bottle found near her bed, apparently in a suicide attempt. She presented with diarrhea, frequent urination, convulsions, breathing difficulties, constricted pupils (miosis), and excessive salivation. Which of the following is correct regarding this patient? A. She most likely consumed an organophosphate pesticide. B. The symptoms are consistent with sympathetic activation. C. Her symptoms can be treated using an anticholinesterase agent. D. Her symptoms can be treated using a cholinergic agonist.

Correct answer = A. The symptoms are consistent with that of cholinergic crisis. Since the elderly female lives on a farm and the symptoms are consistent with a cholinergic crisis (usually caused by cholinesterase inhibitors), it may be assumed that she has consumed an organophosphate pesticide (irreversible cholinesterase inhibitor). Assuming that the symptoms are caused by organophosphate poisoning, administering an anticholinesterase agent or a cholinergic agonist will worsen the condition. The symptoms are not consistent with that of sympathetic activation, as sympathetic activation will cause symptoms opposite to that of cholinergic crisis seen in this patient.

Which strategy is effective to minimize development of HPA axis suppression in a patient with rheumatoid arthritis on long-term high-dose corticosteroid therapy? A. Alternate-day administration B. Administration via topical or inhalation route when possible C. Immediate cessation of the corticosteroid D. Administration of two-thirds of the daily dose in the morning and one-third in the afternoon

Correct answer = A. Topical or inhaled corticosteroids may minimize HPA axis suppression, but are unlikely to be effective in rheumatoid arthritis. Since the patient has been on long-term therapy, a taper would be necessary. Administration of two-thirds of the dose in the morning and one-third in the afternoon is a strategy to mimic the normal diurnal variation of cortisol secretion, but it does not prevent suppression of the HPA axis. Alternate-day administration is beneficial.

An asthma patient was given a nonselective β agonist to relieve bronchoconstriction. Which adverse effect would you expect in this patient? A. Bradycardia B. Tachycardia C. Hypotension (reduction in blood pressure) D. Worsening bronchoconstriction

Correct answer = B. A nonselective β agonist activates both β 1and β 2 receptors. β 1 Activation causes an increase in heart rate (tachycardia), contractility, and subsequent increase in blood pressure. It relieves bronchoconstriction because of the β 2receptor activation.

An elderly man is brought to the emergency room after ingesting a large quantity of prazosin tablets, a drug that blocks α1 adrenergic receptors, which mediate effects of epinephrine and norepinephrine on the blood vessels and urinary bladder. Which symptom is most likely to be seen in this patient? A. Reduced heart rate (bradycardia) B. Dilation of blood vessels (vasorelaxation) C. Increased blood pressure D. Reduction in urinary frequency

Correct answer = B. Activation of α 1 receptors causes vasoconstriction, reduction in urinary frequency, and an increase in blood pressure, without a direct effect on the heart rate. It may cause reflex tachycardia (increase in heart rate) in some patients. Thus blockade of α 1 receptors could theoretically cause dilation of blood vessels, reduction in blood pressure, and increase in urinary frequency. It should not cause a reduction in heart rate.

Which statement correctly describes the proposed mechanism of cardioprotection from low-dose aspirin? A. Aspirin preferentially inhibits COX-2 to lead to a relative reduction in thromboxane A2 levels. B. Aspirin preferentially inhibits COX-1 to lead to a relative reduction in thromboxane A2 levels. C. Aspirin preferentially inhibits COX-2 to lead to a relative reduction in prostacyclin levels. D. Aspirin preferentially inhibits COX-1 to lead a relative reduction in prostacyclin levels.

Correct answer = B. At low doses aspirin selectively inhibits COX-1, which reduces the production of thromboxane A 2, a substance that promotes vasoconstriction and platelet aggregation. COX-2 activity is thought to lead to relatively higher levels of prostacyclin which causes vasodilation and inhibits platelet aggregation. Selective COX-2 inhibitors, as well as all NSAIDs, may increase the risk for CV events by inhibiting the beneficial production of prostacyclin by COX-2, thereby leading to a relative imbalance of thromboxane A 2, and promoting platelet aggregation and vasoconstriction.

Atropa belladonna is a plant that contains atropine (a muscarinic antagonist). Which of the following drugs or classes of drugs will be most useful in treating poisoning with belladonna? A. Malathion B. Physostigmine C. Muscarinic antagonists D. Nicotinic antagonists

Correct answer = B. Atropine is a competitive muscarinic receptor antagonist that causes anticholinergic effects. Muscarinic agonists or any other drugs that increase the levels of ACh are able to counteract effects of atropine. Thus, anticholinesterases such as malathion and physostigmine can counteract the effects of atropine, in theory. However, since malathion is an irreversible inhibitor of acetylcholinesterase, it is not used for systemic treatment in patients. Muscarinic antagonists worsen the toxicity of atropine. Nicotinic antagonists can worsen the toxicity by acting on parasympathetic ganglionic receptors and thus reducing the release of ACh.

A 50-year-old male was in anaphylactic shock after being stung by a hornet. The medical team tried to reverse the bronchoconstriction and hypotension using epinephrine; however, the patient did not fully respond to the treatment. The patient's wife mentioned that he is taking a prescription medication for blood pressure. Which medication is he most likely taking that contributed to a reduced response to epinephrine? A. Doxazosin B. Propranolol C. Metoprolol D. Acebutolol

Correct answer = B. Epinephrine reverses hypotension by activating β 1 receptors and relieves bronchoconstriction by activating β 2 receptors in anaphylaxis. Since epinephrine was not effective in reversing hypotension or bronchoconstriction in this patient, it could be assumed that the patient was on a nonselective β-blocker (propranolol). Doxazosin (α 1-blocker), metoprolol, or acebutolol (both β 1-selective blockers) would not have completely prevented the effects of epinephrine.

Which category of allergic rhinitis medications is most likely to be associated with rhinitis medicamentosa (rebound nasal congestion) with prolonged use? A. Intranasal corticosteroid B. Intranasal decongestant C. Leukotriene antagonist D. Oral antihistamine

Correct answer = B. Intranasal decongestants should be used no longer than 3 days due to the risk of rebound nasal congestion (rhinitis medicamentosa). For this reason, the α-adrenergic agents should not be used in the long-term treatment of allergic rhinitis. The other agents may be used as chronic therapies.

A patient with asthma was prescribed a β2 agonist for acute relief of bronchospasm, but did not respond to treatment. Which drug is the most likely next option for this patient? A. Benztropine B. Ipratropium C. Oxybutynin D. Physostigmine

Correct answer = B. Major receptors present in the bronchial tissues are muscarinic and adrenergic β 2 receptors. Muscarinic activation causes bronchoconstriction, and β 2 receptor activation causes bronchodilation. Therefore, direct or indirect (physostigmine) muscarinic agonists worsen bronchospasm. Ipratropium is a muscarinic antagonist that can relax bronchial smooth muscles and relieve bronchospasm in patients who are not responsive to β 2agonists. Benztropine is used in the treatment of Parkinson disease or relief of extrapyramidal symptoms from antipsychotics. Oxybutynin is used for overactive bladder.

If an ophthalmologist wants to dilate the pupils for an eye examination, which drug/class of drugs is theoretically useful? A. Muscarinic receptor activator (agonist) B. Muscarinic receptor inhibitor (antagonist) C. Pilocarpine D. Neostigmine

Correct answer = B. Muscarinic agonists (for example, pilocarpine) contract the circular smooth muscles in the iris sphincter and constrict the pupil (miosis). Anticholinesterases (for example, neostigmine, physostigmine) also cause miosis by increasing the level of ACh. Muscarinic antagonists, on the other hand, relax the circular smooth muscles in the iris sphincter and cause dilation of the pupil (mydriasis).

. A 60-year-old female who had a cancerous growth in the neck region underwent radiation therapy. Her salivary secretion was reduced due to radiation and she suffers from dry mouth (xerostomia). Which drug would be most useful in treating xerostomia in this patient? A. Acetylcholine B. Pilocarpine C. Echothiophate D. Atropine

Correct answer = B. Salivary secretion may be enhanced by activating muscarinic receptors in the salivary glands. This can be achieved in theory by using a muscarinic agonist or an anticholinesterase agent. Pilocarpine is a muscarinic agonist administered orally for this purpose. Acetylcholine has similar effects as that of pilocarpine; however, it cannot be used therapeutically as it is rapidly destroyed by cholinesterase in the body. Echothiophate is an irreversible cholinesterase inhibitor, but it cannot be used therapeutically because of its toxic effects. Atropine is a muscarinic antagonist and worsens dry mouth.

Which patient is most likely to have suppression of the HPA axis and require a slow taper of corticosteroid therapy? A. A patient taking 40 mg of prednisone daily for 7 days to treat an asthma exacerbation. B. A patient taking 10 mg of prednisone daily for 3 months for rheumatoid arthritis. C. A patient using mometasone nasal spray daily for 6 months for allergic rhinitis. D. A patient receiving an intraarticular injection of methylprednisolone for osteoarthritis.

Correct answer = B. Suppression of the HPA axis usually occurs with higher doses of corticosteroids when used for a duration of 2 weeks or more. Although the dose of prednisone is higher in the asthma patient, the duration of therapy is short, so the risk of HPA axis suppression is lower. The risk of HPA axis suppression is low with topical therapies like intranasal mometasone and with one-time joint injections.

A 40-year-old male presents to his family physician with drooping eyelids, difficulty chewing and swallowing, and muscle fatigue even on mild exertion. Which agent could be used to diagnose myasthenia gravis in this patient? A. Atropine B. Edrophonium C. Pralidoxime D. Echothiophate

Correct answer = B. The function of nicotinic receptors in skeletal muscles is diminished in myasthenia gravis due to the development of antibodies to nicotinic receptors (autoimmune disease). Any drug that increases levels of ACh in the neuromuscular junction can improve symptoms in myasthenia gravis. Thus, edrophonium, a reversible cholinesterase inhibitor with a short duration of action can temporarily improve skeletal muscle weakness in myasthenia gravis, serving as a diagnostic tool. Atropine is a muscarinic antagonist and has no role in skeletal muscle function. Pralidoxime is a drug that is used to reverse the binding of irreversible cholinesterase inhibitors with cholinesterase enzyme and helps to reactivate cholinesterase enzyme. Hence, pralidoxime will not be useful in improving skeletal muscle function in myasthenia gravis.

Which statement concerning the parasympathetic nervous system is correct? A. The parasympathetic system often discharges as a single, functional system. B. The parasympathetic division is involved in near vision, movement of food, and urination. C. The postganglionic fibers of the parasympathetic division are long, compared to those of the sympathetic nervous system. D. The parasympathetic system controls the secretion of the adrenal medulla.

Correct answer = B. The parasympathetic nervous system maintains essential bodily functions, such as vision, movement of food, and urination. It uses acetylcholine, not norepinephrine, as a neurotransmitter, and it discharges as discrete fibers that are activated separately. The postganglionic fibers of the parasympathetic system are short compared to those of the sympathetic division. The adrenal medulla is under the control of the sympathetic system.

A β-blocker was prescribed for hypertension in a patient with asthma. After a week of treatment, the asthma attacks got worse, and the patient was asked to stop taking the β-blocker. Which β-blocker would you suggest as an alternative that is less likely to worsen the asthma? A. Propranolol B. Metoprolol C. Labetalol D. Carvedilol

Correct answer = B. The patient was most likely given a nonselective β-blocker (antagonizes both β 1 and β 2 receptors) that made the asthma worse due to β 2 antagonism. An alternative is to prescribe a cardioselective (antagonizes only β 1) β-blocker that does not antagonize β 2 receptors in the bronchioles. Metoprolol is a cardioselective β-blocker. Propranolol, labetalol, and carvedilol are nonselective β-blockers and could worsen the asthma.

A patient with Addison disease treated with hydrocortisone is experiencing dehydration and hyponatremia. Which drug is best to add to the patient's therapy? A. Dexamethasone B. Fludrocortisone C. Prednisone D. Triamcinolone

Correct answer = B. To combat dehydration and hyponatremia, a corticosteroid with high mineralocorticoid activity is needed. Fludrocortisone has the greatest mineralocorticoid activity of the agents provided. The other drugs have little or no mineralocorticoid activity.

Which of the following classes of adrenergic agents has utility in the management of hypertension? A. α1 Agonist B. α2 Agonist C. β1 Agonist D. β3 Agonist

Correct answer = B. α 2 Agonists activate α 2 receptors located in the presynaptic terminal of sympathetic neurons and cause a reduction in the release of norepinephrine from sympathetic nerve terminals. This leads to a reduction in blood pressure. α 2Agonists such as clonidine and methyldopa are therefore used as antihypertensive agents. α 1 Agonists cause vasoconstriction, and β 1 agonists cause increased cardiac output and renin release, so these agents may increase blood pressure. β3 Agonists are not used in the management of hypertension.

Which of the following is correct regarding α-adrenergic blockers? A. α-Adrenergic blockers are used in the treatment of hypotension in anaphylactic shock. B. α-Adrenergic blockers are used in the treatment of benign prostatic hyperplasia (BPH). C. α-Adrenergic blockers may cause bradycardia. D. α-Adrenergic blockers reduce the frequency of urination.

Correct answer = B. α-Adrenergic blockers are used in the treatment of BPH because of their relaxant effect on prostate smooth muscles. Being antihypertensive agents, they are not useful in treating hypotension in anaphylaxis. α-Adrenergic blockers generally cause reflex tachycardia (not bradycardia) due to the significant drop in blood pressure caused by them. They increase (not reduce) the frequency of urination by relaxing the internal sphincter of the urinary bladder, which is controlled by α 1 receptors.

Which of the following drugs is commonly used topically in the treatment of glaucoma? A. Esmolol B. Timolol C. Silodosin D. Yohimbine

Correct answer = B. β-Blockers reduce the formation of aqueous humor in the eye and therefore reduce intraocular pressure, thus relieving glaucoma. Timolol is a nonselective β-blocker that is commonly used topically to treat glaucoma. Esmolol is a short-acting β-blocker that is used intravenously for hypertension or arrhythmias. Silodosin is an α 1 antagonist used for BPH, and yohimbine is a α 2 antagonist used for sexual dysfunction.

Which statement describes appropriate inhaler technique for a dry powder inhaler? A. Inhale slowly and deeply just before and throughout actuation of the inhaler. B. Use a large-volume chamber (spacer) to decrease deposition of drug in the mouth caused by improper inhaler technique. C. Inhale quickly and deeply to optimize drug delivery to the lungs. D. Rinse mouth in a "swish-and-spit" method with water prior to inhaler use to decrease the chance of adverse events.

Correct answer = C. "Quick and deep" inhalation is required for effective use of a DPI. Inhaling "slowly and deeply" and the use of a spacer describe techniques associated with an MDI, not DPI. Rinsing the mouth may be appropriate for either type of inhaler if the medication being administered is an inhaled corticosteroid; however, this should always be done following inhaler use, not prior to use.

A patient develops urinary retention after an abdominal surgery. Urinary obstruction was ruled out in this patient. Which strategy would be helpful in promoting urination? A. Activating nicotinic receptors B. Inhibiting the release of acetylcholine C. Inhibiting cholinesterase enzyme D. Blocking muscarinic receptors

Correct answer = C. Activation of muscarinic receptors in the detrusor muscle of the urinary bladder can promote urination in patients where the tone of detrusor muscle is low. Inhibiting cholinesterase enzyme increases the levels of acetylcholine, and acetylcholine can increase the tone of the detrusor muscle. There are no nicotinic receptors in the detrusor muscle; therefore, activation of nicotinic receptors is not helpful. Inhibiting the release of acetylcholine or blocking muscarinic receptors worsens urinary retention.

A 9-year-old girl has severe asthma that required three hospitalizations in the past year. She is now receiving therapy that has greatly reduced the frequency of severe attacks. Which drug is most likely responsible for this benefit? A. Inhaled albuterol B. Inhaled ipratropium C. Inhaled fluticasone D. Oral zafirlukast

Correct answer = C. Administration of an inhaled corticosteroid such as fluticasone significantly reduces the frequency of severe asthma attacks. This benefit is accomplished with minimal risk of the severe systemic adverse effects of oral corticosteroid therapy. The β 2agonist albuterol is used to treat acute asthma symptoms. Ipratropium has more common use in COPD and sometimes in the acute management of acute asthma exacerbations. Zafirlukast may reduce the severity of attacks, but not to the same degree or consistency as fluticasone (or other corticosteroids)

Which is the most effective drug for motion sickness for a person planning to go on a cruise? A. Atropine B. Fesoterodine C. Scopolamine D. Tropicamide

Correct answer = C. All muscarinic antagonists (anticholinergic drugs) listed are theoretically useful as antimotion sickness drugs; however, scopolamine is the most effective in preventing motion sickness. Tropicamide mostly has ophthalmic uses, and fesoterodine is used for overactive bladder.

An elderly patient is brought to the emergency room with a blood pressure of 76/60 mm Hg, tachycardia, and low cardiac output. He is diagnosed with acute heart failure. Which of the following drugs is most appropriate to improve his cardiac function? A. Epinephrine B. Fenoldopam C. Dobutamine D. Isoproterenol

Correct answer = C. Among the choices, the ideal drug to increase contractility in acute heart failure is dobutamine, since it is a selective β 1-adrenergic agonist. Fenoldopam is a dopamine agonist used to treat severe hypertension. The other drugs are nonselective adrenergic agonists that could cause unwanted side effects.`

A 30-year-old male patient was brought to the ER with amphetamine overdose. He presented with high blood pressure and arrhythmias. Which drug is the most appropriate to treat the cardiovascular symptoms of amphetamine overdose in this patient? A. Metoprolol B. Prazosin C. Labetalol D. Nebivolol

Correct answer = C. Amphetamine is an indirect adrenergic agonist that mainly enhances the release of norepinephrine from peripheral sympathetic neurons. Therefore, it activates all types of adrenergic receptors (that is, α and β receptors) and causes an increase in blood pressure. Since both α and β receptors are activated indirectly by amphetamine, α-blockers (prazosin) or β-blockers (metoprolol, nebivolol) alone cannot relieve the cardiovascular effects of amphetamine poisoning. Labetalol blocks both α 1 and beta receptors and can minimize the cardiovascular effects of amphetamine overdose.

In Alzheimer disease, there is a deficiency of cholinergic neuronal function in the brain. Theoretically, which strategy is useful in treating symptoms of Alzheimer disease? A. Inhibiting cholinergic receptors in the brain B. Inhibiting the release of acetylcholine in the brain C. Inhibiting the acetylcholinesterase enzyme in the brain D. Activating the acetylcholinesterase enzyme in the brain

Correct answer = C. Because there is already a deficiency in brain cholinergic function in Alzheimer disease, inhibiting cholinergic receptors or inhibiting the release of ACh worsens the condition. Activating the acetylcholinesterase enzyme increases the degradation of ACh, which also worsens the condition. However, inhibiting the acetylcholinesterase enzyme helps to increase the levels of ACh in the brain and thereby relieve the symptoms of Alzheimer disease.

A 60-year-old patient started a new antihypertensive medication. His blood pressure is well controlled, but he complains of fatigue, drowsiness, and fainting when he gets up from the bed (orthostatic hypotension). Which of the following drugs is he most likely taking? A. Metoprolol B. Propranolol C. Prazosin D. Alfuzosin

Correct answer = C. Because they block α 1-mediated vasoconstriction, α-blockers (prazosin) are more likely to cause orthostatic hypotension, as compared to β-blockers (metoprolol, propranolol). Alfuzosin is a more selective antagonist for α 1Areceptors in the prostate and bladder and is less likely to cause hypotension than prazosin.

A 32-year-old man with a history of opioid addiction presents with cough due to a viral upper respiratory system infection. Which is appropriate symptomatic treatment for cough in this patient? A. Guaifenesin/dextromethorphan B. Guaifenesin/codeine C. Benzonatate D. Montelukast

Correct answer = C. Benzonatate suppresses the cough reflex through peripheral action and has no abuse potential. Dextromethorphan, an opioid derivative, and codeine, an opioid, both have abuse potential. Montelukast is not indicated for cough suppression.

A patient who has hypertension and mild asthma attacks bought a herbal remedy for asthma online. He does not take any prescription medications for asthma, but takes a β1-selective blocker for hypertension. The herbal remedy relieves the asthma attacks, but his blood pressure seems to increase despite the β-blocker therapy. Which of the following drugs is most likely present in the herbal remedy? A. Phenylephrine B. Norepinephrine C. Ephedrine D. Salmeterol

Correct answer = C. Both ephedrine and salmeterol can relieve asthma symptoms, as they activate β 2 receptors in the bronchioles and cause bronchodilation. However, salmeterol is a selective β 2 agonist and should not increase blood pressure. By contrast, ephedrine stimulates the release of norepinephrine and acts as a direct agonist at α- and β-adrenergic receptors, thus causing an increase in blood pressure. Phenylephrine (a nonselective α agonist) does not cause bronchodilation, so it would not relieve asthma symptoms. Norepinephrine is a nonselective adrenergic agonist that does not have any stimulatory effects on β 2 receptors. In addition, norepinephrine is not active when given orally.

A child with severe asthma is treated with high-dose inhaled corticosteroids. Which adverse effect is of particular concern? A. Hypoglycemia B. Hirsutism C. Growth suppression D. Cushing syndrome

Correct answer = C. Corticosteroids may retard bone growth. Chronic use of the medication may lead to growth suppression, so linear growth should be monitored periodically. Hyperglycemia, not hypoglycemia, is a possible adverse effect. Hirsutism and Cushing syndrome are unlikely with the dose that the child receives via inhalation

A 70-year-old male is treated with doxazosin for overflow incontinence due to his enlarged prostate. He complains of dizzy spells while getting up from bed at night. Which drug would you suggest as an alternative that may not cause dizziness? A. Propranolol B. Phentolamine C. Tamsulosin D. Terazosin

Correct answer = C. Dizziness in this elderly patient could be due to orthostatic hypotension caused by doxazosin. Tamsulosin is an α 1 antagonist that is more selective to the α 1receptor subtype (α 1A) present in the prostate and less selective to the α 1 receptor subtype (α 1B) present in the blood vessels. Therefore, tamsulosin should not affect blood pressure significantly and may not cause dizziness. Terazosin and phentolamine antagonize both these subtypes and cause significant hypotension as a side effect. Propranolol is a nonselective beta-blocker that is not indicated in overflow incontinence.

Which of the following adrenergic agonists is commonly present in nasal sprays available over-the-counter (OTC) to treat nasal congestion? A. Clonidine B. Albuterol C. Oxymetazoline D. Formoterol

Correct answer = C. Drugs with selective α 1 agonistic activity are commonly used as nasal decongestants because of their ability to cause vasoconstriction in the nasal vessels. Oxymetazoline is an α 1 agonist and therefore the preferred drug among the choices as a nasal decongestant. Clonidine is an α 2agonist, albuterol is a β 2 agonist, and formoterol is a long-acting β 2 agonist.

A 12-year-old girl with asthma presents to the emergency room with complaints of cough, dyspnea, and wheezing after visiting a riding stable. Which is the most appropriate drug to rapidly reverse her bronchoconstriction? A. Inhaled fluticasone B. Inhaled beclomethasone C. Inhaled albuterol D. Intravenous propranolol

Correct answer = C. Inhalation of a rapid-acting β 2 agonist, such as albuterol, usually provides immediate bronchodilation. An acute asthmatic crisis often requires intravenous corticosteroids, such as methylprednisolone. Inhaled corticosteroids such as beclomethasone and fluticasone treat chronic airway inflammation but do not provide any immediate effect. Propranolol is a nonselective β-blocker and would aggravate the bronchoconstriction.

Because of its anti-inflammatory mechanism of action, which drug requires regular administration for the treatment of asthma? A. Tiotropium B. Salmeterol C. Mometasone D. Albuterol

Correct answer = C. Inhaled corticosteroids have direct anti-inflammatory properties on the airways and require regular dosing to be effective. Tiotropium is used more frequently for the treatment of COPD. It does not have anti-inflammatory effects like the corticosteroids. Salmeterol and albuterol are both bronchodilators, but do not have anti-inflammatory properties.

. During an ophthalmic surgical procedure, the surgeon wanted to constrict the pupil using a miotic drug. However, he accidentally used another drug that caused dilation of the pupil (mydriasis). Which drug was most likely used? A. Acetylcholine B. Pilocarpine C. Tropicamide D. Bethanechol

Correct answer = C. Muscarinic agonists such as ACh, pilocarpine, and bethanechol contract the circular muscles of iris sphincter and cause constriction of the pupil (miosis), whereas muscarinic antagonists such as tropicamide prevent contraction of the circular muscles of the iris and cause dilation of the pupil (mydriasis).

A patient who received a nondepolarizing neuromuscular blocker (NMB) for skeletal muscle relaxation during surgery is experiencing mild skeletal muscle paralysis after the surgery. Which drug could reverse this effect of NMBs? A. Pilocarpine B. Bethanechol C. Neostigmine D. Atropine

Correct answer = C. Neuromuscular blockers act by blocking nicotinic receptors on the skeletal muscles. Increasing the levels of ACh in the neuromuscular junctions can reverse the effects of NMBs. Therefore, neostigmine, a cholinesterase inhibitor, could reverse the effects of NMBs. Pilocarpine and bethanechol are preferentially muscarinic agonists and have no effects on the nicotinic receptors. Atropine is a muscarinic antagonist and has no effects on nicotinic receptors.

A 64-year-old man presents with signs and symptoms of an acute gouty flare. Which strategy is the least likely to acutely improve his gout symptoms and pain? A. Naproxen B. Colchicine C. Probenecid D. Prednisone

Correct answer = C. Probenecid is a uricosuric agent indicated to lower serum urate levels to prevent gout attacks. It is not indicated during acute gout flares and should not be started until after the resolution of an acute attack. Naproxen, colchicine, and prednisone all represent viable treatment options that acutely reduce pain and inflammation associated with acute gout attacks.

A 54-year-old man with gout is found to have an issue with renal excretion of uric acid. Which drug is an oral agent that would target the cause of his acute gout attacks? A. Allopurinol B. Febuxostat C. Probenecid D. Pegloticase

Correct answer = C. Probenecid is a uricosuric agent that increases renal excretion by inhibiting the urate-anion exchanger in the proximal tubule, thereby blocking reabsorption of uric acid and facilitating its excretion. Allopurinol and febuxostat are xanthine oxidase inhibitors, which primarily act by decreasing uric acid production. Pegloticase works by increasing renal excretion of uric acid; however, it is an IV infusion.

Sarin is a nerve gas that is an organophosphate cholinesterase inhibitor. Which agent could be used as an antidote to sarin poisoning? A. Pilocarpine B. Carbachol C. Atropine D. Physostigmine

Correct answer = C. Sarin is an organophosphate cholinesterase inhibitor. It causes an increase in ACh levels in tissues that leads to cholinergic crisis through activation of muscarinic and nicotinic receptors. Most symptoms of cholinergic crisis are mediated by muscarinic receptors and, therefore, the muscarinic antagonist atropine is used as an antidote for sarin poisoning. Cholinergic agonists such as pilocarpine, carbachol, and physostigmine (indirect agonists) worsen symptoms of sarin poisoning.

A 68-year-old man has COPD with moderate airway obstruction. Despite using salmeterol twice daily, he reports continued symptoms of shortness of breath with mild exertion. Which agent is an appropriate addition to his current therapy? A. Systemic corticosteroids B. Albuterol C. Tiotropium D. Roflumilast

Correct answer = C. The addition of an anticholinergic bronchodilator to the LABA salmeterol would be appropriate and provide additional therapeutic benefit. Systemic corticosteroids are used to treat exacerbations in patients with COPD, but not recommended for chronic use. The addition of a SABA (albuterol) is less likely to provide additional benefit since the patient is already using medication with the same mechanism of action. Roflumilast is not indicated, since the patient only has moderate airway obstruction.

A 58-year-old woman with COPD has been hospitalized three times in the past year for COPD exacerbations. She reports only mild symptoms between exacerbations. Her regimen for the past year has included inhaled salmeterol twice daily and inhaled tiotropium once daily. Her current FEV1 is below 60%. Which is an appropriate change in her drug therapy? A. Discontinue the tiotropium. B. Discontinue the salmeterol. C. Change the salmeterol to a combination product that includes both a LABA and an inhaled corticosteroid (for example, salmeterol/fluticasone DPI). D. Add theophylline.

Correct answer = C. The addition of an inhaled corticosteroid may provide additional benefit since the patient has significant airway obstruction and frequent exacerbations requiring hospitalization. It is not routinely recommended to discontinue a long-acting bronchodilator unless the patient experiences an adverse effect or experiences no therapeutic benefit. In this case, the patient reports mild symptoms in between exacerbations, suggesting she may benefit from both bronchodilators. Theophylline is an oral bronchodilator that is beneficial to some patients with stable COPD. However, because of its toxic potential, its use is not routinely recommended

Which is correct regarding the sympathetic nervous system? A. It generally mediates body functions in "rest-and-digest" mode. B. The neurotransmitter at the sympathetic ganglion is norepinephrine (NE). C. The neurotransmitter at the sympathetic ganglion is acetylcholine (ACh). D. Sympathetic neurons release ACh in the effector organs.

Correct answer = C. The neurotransmitter at the sympathetic and parasympathetic ganglia is acetylcholine. The sympathetic system generally mediates body functions in "fight or flight" mode, and the parasympathetic system generally mediates body functions in "rest-and-digest" mode. Sympathetic neurons release NE, and parasympathetic neurons release ACh in the effector cells.

A 50-year-old male who is noncompliant with medications was recently diagnosed with chronic obstructive pulmonary disease (COPD). His physician would like to prescribe an inhaled anticholinergic that is dosed once or twice daily. Which drug is most appropriate for this patient? A. Atropine B. Ipratropium C. Tiotropium D. Trospium

Correct answer = C. The physician should prescribe a long-acting muscarinic antagonist (LAMA) so that the patient has to inhale the medication only 1 or 2 times daily. Tiotropium is a LAMA, whereas ipratropium is a short-acting muscarinic antagonist (SAMA). Atropine and trospium are muscarinic antagonists, but are not indicated for pulmonary conditions such as asthma or COPD and are not available as inhaled formulations.

A 64-year-old man presents with mild to moderate musculoskeletal back pain. He states that he has tried acetaminophen without relief. His medical history includes diabetes, hypertension, hyperlipidemia, gastric ulcer (resolved), and coronary artery disease. Which is the most appropriate NSAID regimen to treat this patient's pain? A. Celecoxib B. Indomethacin and omeprazole C. Naproxen and omeprazole D. Naproxen

Correct answer = C. This patient is at high risk of future ulcers, due to the history of gastric ulcer. Therefore, using a regimen that includes an agent that is more COX-2 selective or a proton pump inhibitor is warranted. Therefore, D is incorrect. Choices A and B are incorrect because this patient has significant cardiovascular risk and a history of coronary artery disease. Naproxen is thought of as the safest NSAID regarding cardiovascular disease, though it still can present risks. Therefore, C is correct as it uses the first-choice NSAID with the GI protection of a proton pump inhibitor.

Which statement is correct regarding the difference between acetaminophen and naproxen? A. Acetaminophen has more anti-inflammatory effects compared with naproxen. B. Acetaminophen has more GI side effects but less effects on bleeding compared with naproxen. C. Acetaminophen has less risk for CV events compared with naproxen. D. Acetaminophen has fewer antipyretic effects than naproxen.

Correct answer = C. While acetaminophen inhibits prostaglandin synthesis via COX inhibition, it is inactivated peripherally so it is devoid of systemic GI, CV, and bleeding adverse effects which are hallmarks of NSAIDs like naproxen. However, as acetaminophen is active centrally, it is still able to maintain antipyretic effects similar to other NSAIDs.

Which medication inhibits the action of 5-lipoxygenase and consequently the action of leukotriene B4 and the cysteinyl leukotrienes? A. Cromolyn B. Zafirlukast C. Zileuton D. Montelukast

Correct answer = C. Zileuton is the only 5-lipoxygenase inhibitor available. While zafirlukast and montelukast both inhibit the effects of leukotrienes, they do so by blocking the receptor. Cromolyn inhibits mast cell degranulation and the release of histamine.

Which physiological change occurs when the parasympathetic system is activated? A. Increase in heart rate B. Inhibition of lacrimation (tears) C. Dilation of the pupil (mydriasis) D. Increase in gastric motility

Correct answer = D. Activation of the parasympathetic system causes an increase in gastric motility, increase in fluid secretions, reduction in heart rate, and constriction of the pupil. In the "rest-and-digest" mode, the parasympathetic system is more active, which helps with digestion.

A patient with Alzheimer disease needs treatment for overactive bladder (OAB). Which drug is the best choice for this patient? A. Darifenacin B. Solifenacin C. Tolterodine D. Trospium

Correct answer = D. All of agents for OAB except trospium cross the blood-brain barrier to various degrees and could worsen dementia symptoms in Alzheimer disease. Trospium is a quaternary ammonium compound that minimally crosses the blood-brain barrier.

Which agent is a preferred antihistamine for the management of allergic rhinitis? A. Chlorpheniramine B. Diphenhydramine C. Phenylephrine D. Cetirizine

Correct answer = D. Chlorpheniramine and diphenhydramine are first-generation antihistamines and are usually not a preferred treatment due to their increased risk of adverse effects, such as sedation, performance impairment, and other anticholinergic effects. Phenylephrine is short-acting α-adrenergic agonist ("nasal decongestant"). Cetirizine is a second-generation antihistamine and is generally better tolerated, making it a preferred agent for allergic rhinitis.

Corticosteroids are useful in the treatment of which of the following disorders? A. Cushing syndrome B. Diabetes C. Hypertension D. Inflammatory bowel disease

Correct answer = D. Corticosteroids can increase blood pressure and glucose and are not used in the treatment of hypertension or diabetes. Cushing syndrome is an excess secretion of glucocorticoids. Dexamethasone may be used in the diagnosis of Cushing syndrome, but not its treatment. Corticosteroids reduce inflammation and can be used in the management of inflammatory bowel disease.

Which of the following adrenergic drugs is used in the treatment of overactive bladder? A. Epinephrine B. Dobutamine C. Phenylephrine D. Mirabegron

Correct answer = D. Detrusor muscles in the urinary bladder wall have β 3 receptors. Stimulation of these receptors relaxes the urinary bladder wall and relieves overactive bladder. Mirabegron is a β 3 agonist and therefore used in treating overactive bladder. None of the other drugs listed have β 3 agonist activity.

Which of the following drugs has the highest potential to worsen orthostatic hypotension when given together with prazosin? A. Propranolol B. Atenolol C. Nebivolol D. Labetalol

Correct answer = D. Labetalol is a nonselective β-blocker with α1-blocking activity. Prazosin causes orthostatic hypotension due to its α 1-blockade, which could be enhanced by adding labetalol. Propranolol, atenolol and nebivolol do not have α 1-blocking effects.

Which prostaglandin agent can be used to maintain the patency of the ductus arteriosus in neonates with congenital heart problems while awaiting surgery? A. Misoprostol B. Epoprostenol C. Bimatoprost D. Alprostadil

Correct answer = D. Misoprostol, a PGE 1 analog, is used for GI protection or labor induction. Epoprostenol, a PGI 2 analog, is used for the treatment of pulmonary arterial hypertension. Bimatoprost, a PGF 2α analog, is used topically in the eye for the treatment of open angle glaucoma or on the lashes for hypotrichosis. Alprostadil, a PGE 1 analog, is used to maintain patency of the ductus arteriosus in neonates with congenital heart problems. The drug can also be used for erectile dysfunction.

Which of the following drugs could theoretically improve asthma symptoms? A. Bethanechol B. Pilocarpine C. Pyridostigmine D. Atropine

Correct answer = D. Muscarinic agonists and drugs that increase acetylcholine levels cause constriction of bronchial smooth muscles and could exacerbate asthma symptoms. Bethanechol and pilocarpine are muscarinic agonists, and pyridostigmine is a cholinesterase inhibitor that increases levels of acetylcholine. Atropine is a muscarinic antagonist and therefore does not exacerbate asthma. Theoretically, it should relieve symptoms of asthma (not used clinically for this purpose).

A new antihypertensive drug was tested in an animal model of hypertension. The drug when given alone reduces blood pressure in the animal. Norepinephrine when given in the presence of this drug did not cause any significant change in blood pressure or heart rate in the animal. The mechanism of action of the new drug is similar to which of the following agents? A. Doxazosin B. Clonidine C. Atenolol D. Carvedilol

Correct answer = D. Norepinephrine activates both α 1 and β 1receptors and causes an increase in heart rate and blood pressure. A drug that prevents the increase in blood pressure caused by norepinephrine should be similar to carvedilol that antagonizes both α 1 and β 1 receptors. Doxazosin is an α 1antagonist, clonidine is an α 2 agonist, and atenolol is a β antagonist, and these drugs cannot completely prevent the cardiovascular effects of norepinephrine.

A 12-year-old boy with a peanut allergy is brought to the emergency room after accidental consumption of peanuts. He is in anaphylactic shock. Which of the following drugs is most appropriate to treat this patient? A. Norepinephrine B. Phenylephrine C. Dobutamine D. Epinephrine

Correct answer = D. Norepinephrine has more α agonistic effects and activates mainly α 1, α 2, and β 1 receptors. Epinephrine has more β agonistic effects and activates mainly α1, α 2, β 1, and β 2 receptors. Phenylephrine has predominantly α effects and activates mainly α 1 receptors. Dobutamine mainly activates β 1 receptors and has no significant effects on β 2receptors. Thus, epinephrine is the drug of choice in anaphylactic shock that can both stimulate the heart (β 1activation) and dilate bronchioles (β 2 activation).

Which statement correctly describes the pathophysiologic actions of prostaglandins at a target tissue? A. Promote vasoconstriction in the kidneys. B. Promote sodium and water retention in the kidneys. C. Decrease secretion of mucus at the lining of the stomach. D. Decrease secretion of gastric acid in the stomach.

Correct answer = D. Prostaglandins, specifically PGE 2 and PGI2, cause vasodilation in the renal arteries; a decrease in prostaglandins from NSAIDs can lead to vasoconstriction of renal arteries as well as sodium and water retention. In the stomach, PGI 2 inhibits gastric acid secretion, while PGE 2 and PGF 2α promote secretion of protective mucus at the stomach lining.

Why does the somatic nervous system enable a faster response compared to the ANS? A. Somatic motor neurons have ganglia where neurotransmission is mediated by ACh. B. Somatic motor neurons have ganglia where neurotransmission is mediated by NE. C. Somatic motor neurons are not myelinated. D. Somatic motor neurons are myelinated and do not have ganglia.

Correct answer = D. Somatic motor neurons are myelinated and have no ganglia. This enables faster transmission in the somatic neurons.