Nokea
A competitive antagonist is a substance that:
- A. Interacts receptors and produces submaximal effect
- B. Binds to the same receptor site and progressively inhibits the agonist response
- C. Binds to the nonspecific sites of tissue
- D. Binds to one receptor subtype as an agonist and to another as an antagonist
Correct Answer: B
Rationale: Competitive antagonists compete for the same receptor site, reversibly inhibiting the agonist.
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The nursing instructor is discussing drug therapy in the older adult. What would the instructor tell the students about what could affect therapeutic dosing in an older adult?
- A. Changes in the gastrointestinal (GI) system can reduce drug absorption.
- B. In older adults, drugs enter into circulation more quickly.
- C. In older adults, drugs are distributed to a smaller portion of the tissues.
- D. In older adults, drugs have an increased action
Correct Answer: A
Rationale: GI changes in aging (e.g., reduced motility) decrease absorption, affecting dosing.
Because of their site of action, bile acid sequestering resins:
- A. Should be administered separately from other drugs by at least 4 hours
- B. May increase the risk for bleeding
- C. Both 1 and 2
- D. Neither 1 nor 2
Correct Answer: A
Rationale: Bile acid resins bind drugs in the gut, requiring separation by 4 hours.
Behaviors predictive of addiction to controlled substances include:
- A. Stealing or borrowing another patient's drugs
- B. Requiring increasing doses of opiates for pain associated with malignancy
- C. Receiving refills of a Schedule II prescription on a regular basis
- D. Requesting that only their own primary care provider prescribe for them
Correct Answer: A
Rationale: Stealing/borrowing drugs strongly predicts addiction, unlike cancer-related dose increases or regular refills/provider preference , which may be legitimate.
Administration of exenatide is by subcutaneous injection:
- A. 30 minutes prior to the morning meal
- B. 60 minutes prior to the morning and evening meal
- C. 15 minutes after the evening meal
- D. 60 minutes before each meal daily
Correct Answer: B
Rationale: Exenatide is injected 60 minutes before morning and evening meals to optimize glucose control; timing is incorrect.
A provider may consider testing for CYP2D6 variants prior to starting tamoxifen for breast cancer to:
- A. Ensure the patient will not have increased adverse effects from the tamoxifen
- B. Identify if the patient is a poor metabolizer, potentially reducing conversion to active metabolites
- C. Evaluate risk of drug interactions with tamoxifen
- D. Determine if the patient requires a higher dose due to ultra-rapid metabolism
Correct Answer: B
Rationale: CYP2D6 testing identifies poor metabolizers who may not convert tamoxifen to its active form (endoxifen), impacting efficacy, not just ADRs or interactions .