ATI RN
ATI Pharmacology Across the Lifespan Questions
Question 1 of 5
A 70-year-old patient with hypertension is prescribed clonidine. Clonidine works by:
Correct Answer: A
Rationale: The correct answer is A: Inhibiting the release of norepinephrine in the brainstem. Clonidine is a centrally acting alpha-2 adrenergic agonist that works by inhibiting norepinephrine release in the brainstem, leading to decreased sympathetic outflow and ultimately reducing blood pressure. Choices B, C, and D are incorrect because clonidine does not act by blocking beta-adrenergic receptors in the heart, promoting vasodilation by inhibiting calcium channels, or increasing the excretion of sodium and water in the kidneys. The primary mechanism of clonidine's antihypertensive effect lies in its action on norepinephrine release in the brainstem.
Question 2 of 5
This graph illustrates the dose-response relationship for the effect of the beta agonist isoproterenol on an isolated perfused heart, both alone and in the presence of different fixed concentrations of Drug X. Based upon the data shown, Drug X is most likely a(n):
Correct Answer: B
Rationale: The correct answer is B: Competitive antagonist. This can be determined by observing that the presence of Drug X shifts the dose-response curve for isoproterenol to the right without affecting the maximal response. This indicates competitive antagonism, where Drug X competes with isoproterenol for the same receptor site without affecting the efficacy of isoproterenol. Choice A (Beta agonist) is incorrect because the graph does not show any direct agonistic effect of Drug X. Choice C (Irreversible antagonist) is incorrect because the effect of Drug X is reversible, as shown by the ability of isoproterenol to still elicit a response in the presence of Drug X. Choice D (Noncompetitive antagonist) is incorrect because noncompetitive antagonists typically reduce the maximal response of the agonist, which is not seen in this graph.
Question 3 of 5
A 64-year-old man suffering from benign prostatic hyperplasia presented to his physician complaining of generalized itching. The problem began 1 week earlier, after an afternoon of prolonged sun exposure. The patient reported that the itching was distressing, especially during the night. Physical examination showed an enlarged prostate and no other evidence of ongoing disease. Which of the following drugs would be appropriate for this patient?
Correct Answer: D
Rationale: The correct answer is D: Loratadine. Loratadine is a second-generation antihistamine that is commonly used to relieve symptoms of allergies, including itching. In this case, the patient's generalized itching is likely due to an allergic reaction triggered by sun exposure. Loratadine can help alleviate the itching without causing excessive sedation, making it suitable for an elderly patient. A: Cyproheptadine is a first-generation antihistamine that can cause significant sedation and anticholinergic side effects, making it less ideal for an elderly patient. B: Diphenhydramine is also a first-generation antihistamine that can cause sedation and anticholinergic side effects, which may not be well-tolerated by the elderly patient. C: Famotidine is a histamine-2 (H2) receptor antagonist used to reduce stomach acid production and treat ulcers, not itching related to allergic reactions.
Question 4 of 5
A 43-year-old man with a long history of exertional angina was recently diagnosed with migraine. Which of the following anti-migraine drugs would be contraindicated in this patient?
Correct Answer: C
Rationale: The correct answer is C: Sumatriptan. As a 43-year-old man with a history of exertional angina, sumatriptan is contraindicated due to its potential vasoconstrictive effects, which can exacerbate angina symptoms and increase the risk of cardiovascular events. Aspirin (A) is commonly used for cardiovascular protection. Acetaminophen (B) is a safe option for pain relief in patients with angina. Ibuprofen (D) should be used with caution but is not contraindicated as it mainly affects platelet function rather than causing significant vasoconstriction.
Question 5 of 5
A28-year-old woman who was 26 weeks' pregnant had been recently diagnosed with classic migraine. Which of the following drugs would be appropriate to reduce the frequency and severity of her migraine attacks?
Correct Answer: B
Rationale: The correct answer is B: Propranolol. Propranolol is a beta-blocker commonly used to prevent migraines by reducing the frequency and severity of attacks. It works by blocking the action of certain natural chemicals in the body that trigger migraines. Choice A, Ergonovine, is not indicated for migraine prevention and is used for other purposes. Choice C, Ergotamine, is an older medication with more side effects and contraindications compared to propranolol. Choice D, Valproic acid, is also used for migraine prevention but may not be the best choice for a pregnant woman due to potential risks to the fetus.