Question 1

A patient presents with open-angle glaucoma. Which of the following drugs would most directly lower intraocular pressure by increasing the outflow of aqueous humor through the trabecular meshwork, and what is the mechanism?

Accepted Answer

Pilocarpine, by contracting the ciliary muscle and opening the trabecular meshwork

Question 2

Which of the following best explains why beta-blockers are effective in the chronic management of heart failure?

Accepted Answer

They attenuate toxic effects of chronic sympathetic overactivity, reduce renin secretion, and decrease preload and afterload

Question 3

A patient with hypertension is prescribed prazosin. Which of the following is the primary mechanism by which prazosin lowers blood pressure?

Accepted Answer

Alpha-1 antagonism, causing vasodilation and decreasing total peripheral resistance ($$TPR)$$

Question 4

Which of the following side effects is most likely to occur with the use of a muscarinic agonist such as bethanechol?

Accepted Answer

Diarrhea

Question 5

A patient is experiencing photophobia due to a drug-induced dilated pupil. Which class of autonomic drugs is most likely responsible for this side effect?

Accepted Answer

Alpha-1 agonists

Question 6

Which of the following equations correctly relates blood pressure ($$BP$$), cardiac output ($$CO$$), and total peripheral resistance ($$TPR$$)?

Accepted Answer

$$BP = CO 	imes TPR$$

Question 7

A patient with myasthenia gravis is given edrophonium. What is the mechanism of action of this drug?

Accepted Answer

Reversible, short-acting inhibition of acetylcholinesterase via non-covalent interactions

Question 8

Which of the following drugs would be most appropriate to treat an acute episode of heart failure by increasing cardiac contractility?

Accepted Answer

Dobutamine

Question 9

A patient on a non-selective alpha blocker experiences severe reflex tachycardia. Which of the following best explains this phenomenon?

Accepted Answer

Loss of alpha-2-mediated negative feedback increases norepinephrine release onto beta-1 receptors

Question 10

Which of the following best describes the effect of sotalol in the treatment of supraventricular tachycardia (SVT)?

Accepted Answer

It blocks potassium channels, increasing the refractory period in nodal cells

Question 11

A patient with asthma is prescribed albuterol. Which receptor does this drug primarily target, and what is the expected effect?

Accepted Answer

Beta-2 receptor, causing bronchodilation

Question 12

Which of the following is a plausible consequence of ingesting large amounts of tyramine-containing foods while taking a monoamine oxidase inhibitor (MAOI)?

Accepted Answer

Hypertensive crisis due to excessive norepinephrine release

Question 13

Which of the following drugs is a mixed adrenergic agonist that can be used as a nasal decongestant and may also cause mydriasis?

Accepted Answer

Pseudoephedrine

Question 14

Which of the following best describes the effect of beta-1 adrenergic stimulation on the SA node action potential?

Accepted Answer

Increases cAMP, increasing the slope of Phase 4 and raising heart rate

Question 15

A patient with benign prostatic hyperplasia (BPH) and hypertension is prescribed tamsulosin. What is the primary advantage of tamsulosin over other alpha blockers in this context?

Accepted Answer

It is more selective for alpha-1 receptors in the urinary tract, reducing the risk of orthostatic hypotension

Question 16

Which of the following is a key difference between direct muscarinic agonists and cholinesterase inhibitors?

Accepted Answer

Cholinesterase inhibitors increase acetylcholine at both nicotinic and muscarinic receptors, while direct muscarinic agonists only stimulate muscarinic receptors

Question 17

Which of the following best explains why alpha-1 blockers are not the first choice for treating stable angina pectoris?

Accepted Answer

They trigger a baroreceptor reflex that increases contractility, potentially worsening myocardial oxygen demand

Question 18

Which of the following drugs is a beta-blocker with additional alpha-1 blocking activity, making it useful in heart failure and hypertensive emergencies?

Accepted Answer

Carvedilol

Question 19

A patient is given atropine as an antidote for organophosphate poisoning. What is the primary mechanism by which atropine acts in this scenario?

Accepted Answer

It competitively blocks muscarinic receptors, preventing acetylcholine overstimulation

Autonomic Agents: Mechanisms, Indications, and Clinical Applications

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