ATI RN
Practice ATI B Exam Pharmacology Questions
Question 1 of 5
The mechanism of action of selective estrogen receptor modulators (SERMs), such as raloxifene (Evista), is to
Correct Answer: B
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 2 of 5
A 6-year-old boy is brought to his primary care physician with a history of hay fever and asthma. He usually has two to three attacks per week. For symptom control, he uses an albuterol inhaler, but his parents would like to try something more. They would like him to take something that would lessen the amount of attacks he has. Although corticosteroids would probably work best for prophylaxis, they are contraindicated in children. He is instead given montelukast. How does montelukast work?
Correct Answer: A
Rationale: Montelukast prevents asthma attacks by blocking leukotriene receptors . Leukotrienes drive inflammation; montelukast reduces this, complementing albuterol's acute relief. Muscarinic blockade is ipratropium's action. COX inhibition (C, D) is NSAIDs'. Lipoxygenase inhibition (E) is zileuton's. Montelukast's specificity suits prophylaxis in this child.
Question 3 of 5
A patient comes to the ER with a painful stab wound. The ER resident administers pentazocine for the pain. Soon after administration the patient experiences sweating, restlessness, and an increase in pain sensations. What is the most likely explanation for his symptoms?
Correct Answer: B
Rationale: Pentazocine, a mixed opioid agonist-antagonist, acts as a kappa receptor agonist and a partial mu receptor agonist, providing analgesia in opioid-naive patients. However, in a heroin addict with high mu receptor tolerance, pentazocine's partial antagonism at mu receptors can displace full agonists like heroin, precipitating withdrawal symptoms—sweating, restlessness, and heightened pain perception. Tolerance to pentazocine itself wouldn't typically increase pain; it would reduce efficacy. Pentazocine is an effective analgesic in appropriate contexts, so ineffectiveness isn't the issue. Incorrect dosing might alter efficacy or toxicity but wouldn't specifically cause this withdrawal-like reaction. The patient's history of heroin use explains this response, as pentazocine's antagonist properties disrupt the opioid equilibrium, unmasking withdrawal in a dependent individual.
Question 4 of 5
Discharge planning for the client prescribed tetracycline will include which instruction?
Correct Answer: C
Rationale: Tetracycline is a broad-spectrum antibiotic that can be rendered ineffective if taken with certain substances that interfere with its absorption. Dairy products, such as milk, contain calcium, which binds to tetracycline in the gastrointestinal tract, forming insoluble complexes that prevent the drug from being absorbed into the bloodstream. This interaction significantly reduces its therapeutic efficacy, making it crucial to instruct the client to avoid milk when taking the medication. Similarly, antacids (containing magnesium, aluminum, or calcium) and iron supplements also chelate tetracycline, decreasing its bioavailability, so choices A and B are incorrect and potentially harmful instructions. Reducing vitamin intake is unrelated to tetracycline's administration or efficacy, as vitamins do not typically interfere with its action unless specifically combined with minerals like iron or calcium. Therefore, the priority instruction is to avoid milk, ensuring the drug's effectiveness, which makes choice C the correct and most critical discharge teaching point.
Question 5 of 5
A patient says, 'I have such bad seasonal allergies. Is there anything I can take to keep them from happening?' What information should the nurse provide?
Correct Answer: C
Rationale: Preventing seasonal allergies involves blocking histamine (antihistamines, choice A), reducing inflammation (corticosteroids, choice B), or stabilizing mast cells . Mast cell stabilizers (e.g., cromolyn) prevent histamine release, a proactive approach. Decongestants relieve symptoms, not prevent. Choice C highlights a preventive mechanism, key for allergy management education.