ATI RN
Pharmacology Across the Lifespan ATI Questions
Question 1 of 5
A patient is prescribed atorvastatin for hyperlipidemia. The mechanism of action of atorvastatin involves:
Correct Answer: B
Rationale: The correct answer is B: Inhibiting HMG-CoA reductase. Atorvastatin is a statin drug that works by inhibiting the enzyme HMG-CoA reductase, which is involved in the synthesis of cholesterol in the liver. By inhibiting this enzyme, atorvastatin reduces the production of cholesterol in the body, leading to decreased levels of LDL cholesterol. Choices A, C, and D are incorrect because atorvastatin does not increase cholesterol synthesis, bind bile acids, or directly increase HDL cholesterol levels.
Question 2 of 5
Angina is caused by:
Correct Answer: D
Rationale: The correct answer is D because angina is caused by an inadequate supply of oxygen to the heart muscle, leading to chest pain. Extreme binding of noradrenaline due to upregulation can lead to increased constriction of blood vessels, reducing blood flow to the heart. This exacerbates the oxygen supply-demand imbalance, triggering angina. A: Blocking beta1 receptors with constant noradrenaline binding would decrease the effects of noradrenaline, potentially reducing heart rate and blood pressure, but it would not directly cause angina. B: Activating beta2 receptors would cause vasodilation, increasing blood flow to the heart, which is opposite to the mechanism of angina. C: Beta1 receptors not being active anymore would lead to a decrease in heart rate and contractility, but this state would not directly induce angina.
Question 3 of 5
A 30-year-old man presented to the clinic with a 2-month history of right-side head pain recurring on a weekly basis. His headaches were usually preceded by unformed flashes of light, bilaterally, and were associated with nausea, vomiting, and photophobia. The headaches were not relieved by aspirin or ibuprofen and usually lasted all day unless he was able to sleep. A drug acting on which of the following receptors would be most appropriate to stop the migraine attack in this patient?
Correct Answer: D
Rationale: The correct answer is D: 5-HT1B/1D serotonergic receptors. Migraine headaches are believed to be caused by neurovascular dysfunction involving serotonin pathways. Activating 5-HT1B/1D receptors can help constrict blood vessels and inhibit the release of pro-inflammatory neuropeptides, thus relieving migraine symptoms. Beta-2 adrenergic (choice A) receptors are not typically involved in migraine pathophysiology. GABAergic (choice B) drugs may be used for other types of headaches but are not specific for migraines. M1 cholinergic (choice C) drugs are not commonly used for migraine treatment as they do not target the serotonin pathways involved in migraines.
Question 4 of 5
A48-year-old woman suffering from allergic urticaria started a treatment with loratadine. The decreased synthesis of which of the following substances most likely mediated the therapeutic effect of the drug in the patient's disease?
Correct Answer: C
Rationale: The correct answer is C: Inositol triphosphate. Loratadine is an antihistamine used to treat allergic conditions like urticaria by blocking histamine receptors. Histamine binds to H1 receptors on cells, leading to the activation of phospholipase C, which cleaves phosphatidylinositol 4,5-bisphosphate into inositol triphosphate (IP3) and diacylglycerol. IP3 triggers the release of intracellular calcium stores, leading to various cellular responses including allergic reactions. By blocking histamine receptors, loratadine reduces the synthesis of IP3, hence mediating its therapeutic effect. Choice A (cAMP) is incorrect because loratadine does not directly affect the cAMP pathway. Choice B (cGMP) is incorrect as it is not involved in the mechanism of action of loratadine. Choice D (Cyclooxygenase-1) is incorrect as
Question 5 of 5
A48-year-old woman was admitted to the emergency department because of fever (103.1°F, 39.5°C), flushing, sweating, tremors, and altered consciousness. Medical history indicated that she had been suffering from depression for 8 years, currently treated with paroxetine, and for insomnia, currently treated with zolpidem. The patient also reported that 24 hours earlier, she had self-administered three tablets of a drug given to her by a friend to treat a severe headache. Further exams confirmed the preliminary diagnosis, and an appropriate treatment was started. Which of the following drugs most likely triggered the patient's disorder?
Correct Answer: B
Rationale: Step 1: Recognize the symptoms described in the scenario: fever, flushing, sweating, tremors, altered consciousness. These symptoms are indicative of serotonin syndrome. Step 2: Identify the patient's medications that can contribute to serotonin syndrome: paroxetine (an SSRI) and zolpidem (a CNS depressant). Step 3: Eliminate paroxetine as the trigger as the patient has been on it for a long time without issues. Step 4: Sumatriptan, a serotonin receptor agonist used for migraines, is the likely culprit. It can interact with SSRIs like paroxetine, leading to serotonin syndrome. Step 5: Summary: Acetaminophen (A) and ibuprofen (C) are unlikely to cause serotonin syndrome. Zolpidem (D) is less likely than sumatriptan to trigger serotonin syndrome in this case. Thus, the correct answer is B.