ATI RN
Basic Principles of Pharmacology Quizlet Questions
Question 1 of 5
Which of the following statements about the major distribution barriers (blood-brain or fetal-placental) is true?
Correct Answer: B
Rationale: The correct answer is B because the blood-brain barrier is designed to restrict the passage of many drugs into and out of brain cells, regulating the entry of substances to protect the brain from harmful agents. Explanation: 1. The blood-brain barrier is a specialized structure that tightly regulates the passage of substances from the bloodstream into the brain. 2. Many drugs, especially water-soluble and ionized ones (choice A), face difficulty crossing this barrier due to their properties. 3. The fetal-placental barrier (choice C) primarily protects the fetus from harmful substances but does not slow drug entry into brain cells. 4. Lipid-soluble drugs (choice D) can actually pass through these barriers easily due to their chemical properties, posing risks for pregnant women. In summary, choice B is correct as it accurately describes the role of the blood-brain barrier in controlling drug entry into brain cells, while the other choices present inaccurate statements regarding these distribution barriers.
Question 2 of 5
Actions taken to reduce drug-drug interaction problems include all of the following EXCEPT:
Correct Answer: C
Rationale: The correct answer is C because prescribing a third drug to counteract the adverse reaction of the combination does not address the root cause of the drug-drug interaction. It may lead to further complications and potentially more interactions. Reducing the dose of one drug (A) or both drugs (D) and scheduling their administration at different times (B) are effective strategies to minimize drug-drug interactions by adjusting the dosing regimen.
Question 3 of 5
An agonist activates a receptor and stimulates a response. When given frequently over time the body may:
Correct Answer: D
Rationale: The correct answer is D: Down-regulate the numbers of that specific receptor. Step 1: When an agonist continuously activates a receptor, the body may reduce the number of receptors to maintain homeostasis. Step 2: Down-regulation is a feedback mechanism to decrease receptor sensitivity due to excessive stimulation. Step 3: This helps prevent overstimulation and desensitization of the receptor. Summary: A: Up-regulating the total number of receptors is unlikely as the body typically down-regulates in response to prolonged agonist exposure. B: Blocking the receptor with a partial agonist is not a typical response to repeated agonist exposure. C: Altering the drug's metabolism is not directly related to receptor down-regulation in response to agonist stimulation.
Question 4 of 5
The major reason for not crushing a sustained release capsule is that, if crushed, the coated beads of the drugs could possibly result in:
Correct Answer: B
Rationale: The correct answer is B: Toxicity. Crushing a sustained-release capsule can disrupt the controlled release mechanism, leading to the rapid release of a potentially toxic dose. This can overwhelm the body's ability to metabolize the drug safely, causing toxicity. Disintegration (A) would not be the major concern as the beads would still release the drug. Malabsorption (C) is less likely as the drug would still be absorbed, albeit possibly too quickly. Deterioration (D) refers to physical changes in the drug, not toxicity.
Question 5 of 5
An advantage of prescribing a sublingual medication is that the medication is:
Correct Answer: A
Rationale: The correct answer is A: Absorbed rapidly. Sublingual medication is absorbed directly into the bloodstream through the mucous membranes under the tongue, bypassing the digestive system and liver first-pass metabolism. This route allows for faster onset of action and higher bioavailability compared to oral ingestion. Excretion rate (option B) and distribution pattern (option D) are not specific advantages of sublingual administration. While metabolism may be reduced (option C), the primary advantage is the rapid absorption.