521 Final Multiple Choice Questions
. Indicate the drug, which is a direct-acting both alpha- and beta-receptor agonist: a) Norepinephrine b) Methoxamine c) Isoproterenol d) Ephedrine
A
032. Both Metoprolol and atenolol: a) Are members of the beta1-selective group b) Are nonselective beta antagonists c) Have intrinsic sympathomimetic activity d) Have an anesthetic action
A
All of the following factors influence the action of local anesthetics except a. acetylcholinesterase activity in the region of the injection site b. blood flow through tissue in which the injection is made c. dose of local anesthetic injected d. use of vasoconstrictors e. tissue pH
A
Beta-blocking agents may have all of the following effects except: a) Increase plasma concentrations of HDL and decrease of VLDL b) Bronchoconstriction c) Decrease of aqueous humor production d) "membrane-stabilizing" action
A
Beta2 receptor stimulation includes all of the following effects EXCEPT: a) Stimulation of renin secretion b) Fall of potassium concentration in plasma c) Relaxation of bladder, uterus d) Tachycardia
A
Catecholamine includes the following EXCEPT: a) Ephedrine b) Epinephrine c) Isoproterenol d) Norepinephrine
A
Compared with Phentolamine, Alfuzosin has all of the following features EXCEPT: a) Irreversible blockade of alpha receptors b) Highly selective for alpha1 receptors c) The relative absence of tachycardia d) Selective block of alpha1 receptors
A
Compared with epinephrine, ephedrine produces all of the following features EXCEPT: a) It is just a direct-acting sympathomimetic b) It has oral activity c) It is resistant to MAO and has much longer duration of action d) Its effects are similar to epinephrine, but it is less potent
A
Distribution of alpha adrenoreceptor subtypes is associated with all of the following tissues except those of: a) Heart b) Blood vessels c) Prostate d) Pupillary dilator muscle
A
Epinephrine produces all of the following effects EXCEPT: a) Decrease in oxygen consumption b) Bronchodilation c) Hyperglycemia d) Mydriasis
A
In which of the following tissues both alpha and beta1 adrenergic stimulation produce same effect? a. blood vessels b. intestine c. uterus d. bronchial muscles
A
Indicate the sympathomimetic agent, which is combined with a local anesthetic to prolong the duration of infiltration nerve block: a) Epinephrine b) Xylometazoline c) Isoproterenol d) Dobutamine
A
The adverse effects of sympathomimetics include all of the following EXCEPT: a) Drug-induced parkinsonism b) Cerebral hemorrhage or pulmonary edema c) Myocardial infarction d) Ventricular arrhythmias
A
The principal mechanism of action of adrenoreceptor antagonists is: a) Reversible or irreversible interaction with adrenoreceptors b) Depletion of the storage of catecholamines c) Blockade of the amine reuptake pumps d) Nonselective MAO inhibition
A
When given to a patient, phentolamine blocks which one of the following? (A) Bradycardia induced by phenylephrine (B) Bronchodilation induced by epinephrine (C) Increased cardiac contractile force induced by norepinephrine (D) Miosis induced by acetylcholine (E) Vasodilation induced by isoproterenol
A
Which of the following agents is an alpha2-selective antagonist? a) Yohimbine b) Tamsulosin c) Tolazoline d) Prazosin
A
Which of the following drugs has both alpha-selective and beta-blocking effects? a) Labetalol b) Betaxolol c) Propranolol d) Timolol
A
Which of the following drugs is a reversible nonselective alpha and beta antagonist? a) Labetalol b) Phentolamine c) Metoprolol d) Propranolol
A
Which of the following effects is associated with beta3-receptor stimulation? a) Lipolysis b) Decrease in platelet aggregation c) Bronchodilation d) Tachycardia
A
Which of the following statement is not correct? a) Alpha agonists cause miosis b) Alpha agonists cause mydriasis c) Beta antagonists decrease the production of aqueous humor d) Alpha agonists increase the outflow of aqueous humor from the eye
A
Which of the following sympathomimetics is a beta2-selective agonist? a) Terbutaline b) Xylometazoline c) Isoproterenol d) Dobutamine
A
Which of the following sympathomimetics is used in the therapy of bronchial asthma? a) Formoterol b) Norepinephrine c) Methoxamine d) Dobutamine
A
Which of the following topical decongestant agents is an alpha1-selective agonist? a) Phenylephrine b) Clonidine c) Ephedrine d) Epinephrine
A
. A group of volunteers are involved in a phase 1 clinical trial of a new autonomic drug. When administered by intravenous bolus, the blood pressure increases. When given orally for 1 week, the blood pressure decreases. Which of the following standard agents does the new drug most resemble? (A) Atropine (B) Clonidine (C) Phentolamine (an α blocker) (D) Phenylephrine (E) Propranolol (a β blocker)
B
. A nonselective beta receptor agonist causes all of the following effects EXCEPT: a) Increase cardiac output b) Increase peripheral arterial resistance c) Decrease peripheral arterial resistance d) Decrease the mean pressure
B
. Propranolol has all of the following cardiovascular effects EXCEPT: a) It decreases cardiac work and oxygen demand b) It reduces blood flow to the brain after chronic treatment c) It inhibits the renin secretion d) It increases the atrioventricular nodal refractory period
B
. Which of the following beta receptor antagonists is preferable in patients with asthma, diabetes or peripheral vascular diseases? a) Propranolol b) Metoprolol c) Nadolol d) Timolol
B
035. Pindolol and Penbutolol have all of the following properties EXCEPT: a) They are nonselective beta antagonists b) They have no partial agonist activity c) They are less likely to cause bradycardia and abnormalities in plasma lipids d) They are effective in hypertension and angina
B
A child requires multiple minor surgical procedures involving the nasopharynx. Which drug has high surface local anesthetic activity and intrinsic vasoconstrictor actions that reduce bleeding in mucus membranes? a. bupivacaine b. cocaine c. lidocaine d. mepivacaine e. tetracaine
B
A patient on a diagnostic test for myasthenia gravis would be expected to have improved neuromuscular function after being treated with: a. donepezil b. edrophonium c. atropine d. echthiphate e. neostigmine
B
Beta-receptor antagonists have all of the following cardiovascular effects EXCEPT: a) The negative inotropic and chronotropic effects b) Acute effects of these drugs include a fall in peripheral resistance c) Decrease sympathetic outflow from the CNS d) Reduction of the release of renin
B
Beta1 receptor stimulation includes all of the following effects EXCEPT: a) Increase in heart contractility b) Bronchodilation c) Tachycardia d) Increase in conduction velocity in the atrioventricular node
B
Characteristics of epinephrine include all of the following EXCEPT: a) It is synthesized into the adrenal medulla b) It is mainly synthesized into the nerve ending c) It is transported in the blood to target tissues d) It directly interacts with and activates adrenoreceptors
B
Characteristics of oxymetazoline include all of the following EXCEPT: a) It is a direct-acting alpha1-receptor agonist b) It increases heart rate, contractility and cardiac output c) It causes reflex bradycardia d) It increases total peripheral resistance
B
Characteristics of phentolamine include all of the following EXCEPT: a) Reduction in peripheral resistance b) Stimulation of responses to serotonin c) Tachycardia d) Stimulation of muscarinic, H1 and H2 histamine receptors
B
Clinical studies have shown that adrenoceptor blockers have many useful effects in patients. However, a number of drug toxicities have been documented. Adverse effects that limit the use of adrenoceptor blockers include which one of the following? (A) Bronchoconstriction from α-blocking agents (B) Acute heart failure exacerbation from β blockers (C) Impaired blood sugar response with α blockers (D) Increased intraocular pressure with β blockers (E) Sleep disturbances from α-blocking drugs
B
Ephedrine causes: a) Miosis b) Bronchodilation c) Hypotension d) Bradycardia
B
Epinephrine decreases intracellular cAMP levels by acting on: a) α1 receptor b) α2 receptor c) beta1 receptor d) beta2 receptor
B
Indicate a beta receptor antagonist with intrinsic sympathomimetic activity: a) Propranolol b) Pindolol c) Metoprolol d) Carvedilol
B
Indicate an alpha-receptor antagonist, which binds covalently to alpha receptors, causing irreversible blockade of long duration (14-48 hours or longer): a) Phentolamine b) Phenoxybenzamine c) Ergotamine d) Prazosin
B
Indicate the beta1-selective agonist: a) Isoproterenol b) Dobutamine c) Metaproterenol d) Epinephrine
B
Indicate the beta1-selective antagonist: a) Propranolol b) Metoprolol c) Carvedilol d) Sotalol
B
Indicate the indirect-acting adrenoreceptor blocking drug: a) Tolazoline b) Reserpine c) Carvedilol d) Prazosin
B
The principal adverse effects of phentolamine include all of the following EXCEPT: a) Diarrhea b) Bradycardia c) Arrhythmias d) Myocardial ischemia
B
The principal mechanism of phentolamine-induced tachycardia is: a) Antagonism of presynaptic alpha2 receptors enhances norepinephrine release, which causes cardiac stimulation via unblocked beta receptors b) Baroreflex mechanism c) Direct effect on the heart by stimulation of beta1 receptors d) Inhibition of transmitter reuptake at noradrenergic synapses
B
Which of the following agents is an alpha2-selective agonist? a) Norepinephrine b) Clonidine c) Ritodrine d) Ephedrine
B
Which of the following alpha receptor antagonists is useful in reversing the intense local vasoconstriction caused by inadvertent infiltration of norepinephrine into subcutaneous tissue during intravenous administration? a) Propranolol b) Phentolamine c) Tamsulosin d) Ergotamine
B
Which of the following are probable signs of the anaphylactic reaction to bee stings? (A) Bronchodilation, tachycardia, hypertension, vomiting, diarrhea (B) Bronchospasm, tachycardia, hypotension, laryngeal edema (C) Diarrhea, bradycardia, vomiting (D) Laryngeal edema, bradycardia, hypotension, diarrhea (E) Miosis, tachycardia, vomiting, diarrhea
B
Which of the following drugs causes bronchodilation without significant cardiac stimulation? a) Isoproterenol b) Terbutaline c) Xylometazoline d) Clonidine
B
Which of the following drugs is nonselective alpha receptor antagonist? a) Prazosin b) Phentolamine c) Metoprolol d) Reserpine
B
Which of the following statements is not correct? a) Epinephrine acts on both alpha- and beta-receptors b) Norepinephrine has a predominantly beta action -mixed alpha and beta agonist c) Phenylephrine has a predominantly alpha action d) Isoproterenol has a predominantly beta action
B
Which of the following sympathomimetics is an effective mydriatic? a) Salmeterol b) Phenylephrine c) Dobutamine d) Norepinephrine
B
Which of the following sympathomimetics is preferable for the emergency therapy of cardiogenic shock? a) Ephedrine b) Dobutamine c) Isoproterenol d) Methoxamine
B
Which statement about speed of onset of nerve blockage with local anesthetics is correct? a. faster in hypercalcemia b. faster in myelinated fibers c. faster in tissues that are infected d. slower in hyperkalemia e. slower in sensory than motor nerves
B
Characteristics of dobutamine include all of the following EXCEPT: a) It is a relatively beta1-selective synthetic catecholamine b) It is used to treat bronchospasm c) It increases atrioventricular conduction d) It causes vasodilation in renal blood vessels by acting on D1 receptors.
B, D
. Beta-receptor blocking drugs are used in the treatment all of the following diseases EXCEPT: a) Hypertension, ischemic heart disease, cardiac arrhythmias b) Glaucoma c) Pheochromocytoma d) Hyperthyroidism
C
A new drug was administered to an anesthetized animal with the results shown here. A large dose of epinephrine (epi) was administered before and after the new agent for comparison. Which of the following agents does the new drug most closely resemble? (A) Atenolol (B) Atropine (C) Labetalol (D) Phenoxybenzamine (E) Propranolol
C
A patient is to receive epinephrine. She has previously received an adrenoceptor-blocking agent. Which of the following effects of epinephrine would be blocked by phentolamine but not by metoprolol? (A) Cardiac stimulation (B) Increase of cAMP (cyclic adenosine monophosphate) in fat (C) Mydriasis (D) Relaxation of bronchial smooth muscle (E) Relaxation of the uterus
C
A relatively pure alpha agonist causes all of the following effects EXCEPT: a) Increase peripheral arterial resistance b) Increase venous return c) Has no effect on blood vessels d) Reflex bradycardia
C
A vasoconstrictor added to a solution of lidocaine for a peripheral nerve block will a. decrease risk of seizure b. increase duration of anesthetic action of local anesthetic c. both A and B d. neither A nor B
C
All of the following agents are beta receptor agonists EXCEPT: a) Epinephrine b) Isoproterenol c) oxymetazoline d) Dobutamine
C
Beta adrenoreceptor subtypes are contained in all of the following tissues EXCEPT: a) Bronchial muscles b) Heart c) Pupillary dilator muscle d) Fat cells
C
Beta-receptor antagonists cause: a) Stimulation of lipolysis b) Stimulation of gluconeogenesis c) Inhibition of glycogenolysis d) Stimulation of insulin secretion
C
Characteristics of alpha-receptor antagonists include all of the following EXCEPT: a) They cause a fall in peripheral resistance and blood pressure b) They cause epinephrine reversal (convert a pressor response to a depressor response) c) Bronchospasm d) They may cause postural hypotension and reflex tachycardia
C
Characteristics of beta-blocking agents include all of the following EXCEPT: a) They occupy beta receptors and competitively reduce receptor occupancy by catecholamines or other beta agonists b) They do not cause hypotension in individuals with normal blood pressure c) They induce depression and depleted stores of catecholamines d) They can cause blockade in the atrioventricular node
C
Characteristics of salmeterol include all of the following EXCEPT: a) It is a potent selective beta2 agonist b) It causes uterine relaxation c) It stimulates heart rate, contractility and cardiac output d) It is used in the therapy of asthma
C
Direct effects on the heart are determined largely by: a) Alpha1 receptor b) Alpha2 receptor c) Beta1 receptor d) Beta2 receptor
C
Drug Y had the effects shown in the table below. In the Animal Receiving Heart Rate Response to Drug Y No pretreatment ↑ Hexamethonium ↑ Atropine ↑ Phenoxybenzamine ↑ Drug Y is probably a drug similar to (A) Acetylcholine (B) Edrophonium (C) Isoproterenol (D) Succinylcholine (E) Prazosin
C
Epinephrine produces all of the following effects EXCEPT: a) Positive inotropic and chronotropic actions on the heart b) Increase peripheral resistance c) Uterine contraction d) Skeletal muscle blood vessel dilatation
C
If this child has signs of anaphylaxis, what is the treatment of choice? (A) Diphenhydramine (an antihistamine) (B) Ephedrine (C) Epinephrine (D) Isoproterenol (E) Methylprednisolone (a corticosteroid)
C
Indicate the alpha1-selective antagonist: a) Phentolamine b) Dihydroergotamine c) Prazosin d) Labetalol
C
Indicate the beta adrenoreceptor antagonist, which has partial beta-agonist activity: a) Propranolol b) Metoprolol c) Pindolol -ISA d) Betaxolol
C
Indicate the indirect-acting sympathomimetic agent: a) Epinephrine b) Phenylephrine c) Ephedrine d) Isoproterenol
C
Indicate the sympathomimetic, which may be useful in the emergency management of cardiac arrest: a) Methoxamine b) Phenylephrine c) Epinephrine d) Xylometazoline
C
Indirect action includes all of the following properties EXCEPT: a) Displacement of stored catecholamines from the adrenergic nerve ending b) Inhibition of reuptake of catecholamines already released c) Interaction with adrenoreceptors d) Inhibition of the metabolism of endogenous catecholamines from peripheral adrenergic neurons
C
Isoproterenol produces all of the following effects EXCEPT: a) Increase in cardiac output b) Fall in diastolic and mean arterial pressure c) Bronchoconstriction d) Tachycardia
C
Nonselective alpha-receptor antagonists are most useful in the treatment of: a) Asthma b) Cardiac arrhythmias c) Pheochromocytoma d) Chronic hypertension
C
Propranolol-induced adverse effects include all of the following EXCEPT: a) Bronchoconstriction b) "Supersensitivity" of beta-adrenergic receptors c) Hyperglycemia d) Sedation, sleep disturbances, depression and sexual dysfunction
C
Pyridostigmine and neostigmine may case which one of the following in the crop duster pilot exposed to organophsophates: a. bronchodilation b. mydriasis c. diarrhea d. irreversibel inhibition of acetylcholinesterase e. reduced gastric acid secretion
C
Selective alpha1 receptor antagonists such as tamsulosin, terazosin, alfuzosin are efficacious in: a) Hyperthyroidism b) Cardiac arrhythmias c) Benign prostatic hyperplasia (BPH) d) Asthma
C
Which of the following agents is a nonselective beta receptor agonist? a) Norepinephrine b) Terbutaline c) Isoproterenol d) Dobutamine
C
Which of the following agents is an alpha1, alpha2, beta1, and beta2 receptor agonist? a) Methoxamine b) Albuterol c) Epinephrine d) Norepinephrine
C
Which of the following direct-acting drugs is a relatively pure alpha agonist, an effective mydriatic and decongestant and can be used to raise blood pressure? a) Epinephrine b) Norepinephrine c) Phenylephrine d) Ephedrine
C
Which of the following drugs is a nonselective beta receptor antagonist? a) Metoprolol b) Atenolol c) Propranolol d) Acebutolol
C
Which of the following drugs is useful in the treatment of pheochromocytoma? a) Phenylephrine b) Propranolol c) Phentolamine d) Epinephrine
C
Which of the following effects is related to direct beta1-adrenoreceptor stimulation? a) Bronchodilation b) Vasodilatation c) Tachycardia d) Bradycardia
C
Which of the following sympathomimetics acts indirectly? a) Epinephrine b) Norepinephrine c) Ephedrine d) Methoxamine
C
Which of the following sympathomimetics is preferable for the treatment of chronic orthostatic hypotension? a) Epinephrine b) Norepinephrine c) Midodrine d) Salmeterol
C
Which of the following sympathomimetics is related to short-acting topical decongestant agents? a) Albuterol b) Terbutaline c) Phenylephrine d) Norepinephrine
C
A 30-year-old man has been treated with several autonomic drugs for 4 weeks. He is now admi0ed to the emergency department showing signs of drug toxicity. Which of the following signs would disJnguish between an overdose of a ganglion blocker versus a muscarinic blocker? (A) Cycloplegia (B) Dry skin in a warm environment (C) Miosis (D) Postural hypotension (E) Tachycardia
D
A 50 year old male farm worker is brought to emergency room. He was found confused in orchard and since then lost consciousness. His HR is 45 and BP is 80/40. He is sweating and salivating profusely. Which one of the following treatments is indicated? a. physostigmine b. NE c. trimethaphan d. atropine e. edrophonium
D
A 56-year-old man has hypertension and an enlarged prostate, which biopsy shows to be benign prostatic hyperplasia. He complains of urinary retention. Which of the following drugs would be the most appropriate initial therapy? (A) Albuterol (B) Atenolol (C) Metoprolol (D) Prazosin (E) Timolol
D
A bronchial smooth muscle contains: a) Alpha1 receptor b) Alpha2 receptor c) Beta 1 receptor d) Beta 2 receptor
D
Beta-blocker-induced adverse effects include all of the following EXCEPT: a) Bronchoconstriction b) Depression of myocardial contractility and excitability c) "Supersensitivity" of beta-receptors associated with rapid withdrawal of drugs d) Hyperglycemia
D
Beta-blocking drugs-induced chronically lower blood pressure may be associated with theirs effects on: a) The heart b) The blood vessels c) The renin-angiotensin system d) All of the above
D
Characteristic properties of local anesthetics include all the following except: a. increase in membrane refractory period b. blockage of voltage dependent Na channels c. binding to Na channel from inner membrane side d. preferential binding to resting channels e. slowing of axonal impulse conduction
D
Characteristics of ephedrine include all of the following EXCEPT: a) It acts primarily through the release of stored cathecholamines b) It is a mild CNS stimulant c) It causes tachyphylaxis with repeated administration d) It decreases arterial pressure
D
Four new synthetic drugs (designated W, X, Y, and Z) are to be studied for their cardiovascular effects. They are given to 4 anesthetized animals while the heart rate is recorded. The first animal has received no pretreatment (control); the second has received an effective dose of hexamethonium; the third has received an effective dose of atropine; and the fourth has received an effective dose of Phenoxybenzamine. The net changes induced by W, X, Y, and Z in the animals are described in the following questions. Drug W increased heart rate in the control animal, the atropine-pretreated animal, and the phenoxybenzamine pretreated animal. However, drug W had no effect on heart rate in the hexamethonium-pretreated animal. Drug W is probably a drug similar to (A) Acetylcholine (B) Edrophonium (C) Isoproterenol (D) Nicotine (E) NE
D
Indicate adrenoreceptor antagonist agents, which are used for the management of pheochromocytoma: a) Selective beta2-receptor antagonists b) Nonselective beta-receptor antagonists c) Indirect-acting adrenoreceptor antagonist drugs d) alpha-receptor antagonists
D
Indicate an alpha receptor antagonist, which is an efficacious drug in the treatment of mild to moderate systemic hypertension: a) Phentolamine b) Phenoxybenzamine c) Ergotamine d) Prazosin
D
Indicate the agent of choice in the emergency therapy of anaphylactic shock: a) Methoxamine b) Terbutaline c) Phenylephrine d) Epinephrine
D
Indicate the direct-acting sympathomimetic, which is an alpha1, alpha2, and beta1 receptor agonist: a) Isoproterenol b) Ephedrine c) Dobutamine d) Norepinephrine
D
Indicate the irreversible alpha receptor antagonist: a) Tolazoline b) Labetalol c) Prazosin d) Phenoxybenzamine
D
Indicate the long-acting topical decongestant agents: a) Epinephrine b) Norepinephrine c) Isoproterenol d) Xylometazoline
D
Indicate the sympathomimetic drug, which is used in a neurogenic hypotensive emergency: a) Xylometazoline b) Ephedrine c) Terbutaline d) Phenylephrine
D
Indicate the sympathomimetic, which may cause hypotension, presumably because of a clonidine-like effect: a) Epinephrine b) Phenylephrine c) Xylometazoline d) Isoproterenol
D
Isoproterenol is: a) Both an alpha- and beta-receptor agonist b) beta1-selective agonist c) beta2-selective agonist d) Nonselective beta receptor agonist
D
Propranolol is used in the treatment of all the following diseases EXCEPT: a) Cardiovascular diseases b) Hyperthyroidism c) Migraine headache d) Bronchial asthma
D
Sympathetic stimulation is mediated by: a) Release of norepinephrine from nerve terminals b) Activation of adrenoreceptors on postsynaptic sites c) Release of epinephrine from the adrenal medulla d) All of the above
D
The effects of sympathomimetics on blood pressure are associated with their effects on: a) The heart rate b) The peripheral resistance c) The cardiac output d) All of the above
D
Which of the following drugs is a potent competitive antagonist at both alpha1 and alpha2 receptors? a) Prazosin b) Labetalol c) Phenoxybenzamine d) Phentolamine
D
Which of the following statements is not correct? a) Alpha receptors increase arterial resistance, whereas beta2 receptor promote smooth muscle relaxation b) The skin and splanchnic vessels have predominantly alpha receptors c) Vessels in a skeletal muscle may constrict or dilate depending on whether alpha or beta2 receptors are activated d) Nasal mucosa blood vessels have predominantly beta receptors and constrict in the presence of epinephrine and norepinephrine
D
Your 30-year-old patient has moderately severe new onset asthma, and the physician prescribes a highly selective β2 agonist inhaler to be used when needed. In considering the possible drug effects in this patient, you would note that β2 stimulants can cause (A) Direct stimulation of renin release (B) Hypoglycemia (C) Itching due to increased cGMP (cyclic guanine monophosphate) in mast cells (D) Skeletal muscle tremor (E) Vasodilation in the skin
D
A crop duster pilot accidentally exposed to high concentration of highly toxic organophsophate insecticide. If untreated the cause of death from such exposure would probably be: a. cardiac arrhytmia b. GI bleeding c. Heart failure d. hypotension e. Resp. failure
E
Nondepolarizing neuromuscular blockage are associated with all the following except: a. effects are reversed by acetylcholinesterase inhibitors b. intermediate to long duration of action c. bind but do not activate ACh receptor d. most of these agents have minimal CV effects e. initial activation of ACh receptor and depolarization of the motor end plate
E
The most important effect of inadvertent IV administration of a large dose of bupivacaine is: a. bronchoconstriction b. methemoglobinemia c. renal failure d. seizures e. arrhytmia
E
Which of the following is a direct-acJng cholinomimeJc that is lipid-soluble and is used to facilitate smoking cessaJon? (A) Acetylcholine (B) Bethanechol (C) NeosJgmine (D) PhysosJgmine (E) Varenicline
E
Which of the following statements is most correct regarding β-blocking drugs? (A) Labetalol is a selective β2 blocker (B) Metoprolol blocks β2 receptors selectively (C) Nadolol lacks β2-blocking action (D) Pindolol is a β antagonist with high membrane-stabilizing (local anesthetic) activity (E) Timolol lacks the local anesthetic effects of propranolol
E
