Nokea
An agonist activates a receptor and stimulates a response. When given frequently over time, the body may:
- A. Upregulate the total number of receptors
- B. Block the receptor with a partial agonist
- C. Alter the drug's metabolism
- D. Downregulate the numbers of that specific receptor
Correct Answer: D
Rationale: Choice D is correct because frequent agonist use can cause the body to downregulate receptors, reducing sensitivity to overstimulation as a compensatory mechanism. Choice A is incorrect as upregulation occurs with antagonists, not agonists. Choice B is wrong because partial agonists compete, not result from frequent use. Choice C is incorrect since metabolism changes aren't the primary receptor response.
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A 4-month-old infant has a viral illness with high fever and cough. The infant's parent asks the NP about what to give the infant to help with symptoms. The NP should prescribe which of the following?
- A. Aspirin to treat the fever
- B. Acetaminophen as needed
- C. Dextromethorphan for coughing
- D. An antibiotic to prevent increased infection
Correct Answer: B
Rationale: The correct answer is B because acetaminophen is safe for infants to reduce fever. Choice A is incorrect (aspirin risks Reye’s syndrome). Choice C is wrong (dextromethorphan risks respiratory depression). Choice D is inaccurate (antibiotics don’t treat viral illness).
Generic drugs may differ from brand-name drugs in:
- A. Active ingredient
- B. Inactive ingredients
- C. Therapeutic effect
- D. All of the above
Correct Answer: B
Rationale: Choice B is correct because generics may use different inactive ingredients (e.g., fillers, dyes) affecting appearance or tolerability, but not efficacy, per FDA rules. Choice A is incorrect as active ingredients must be identical. Choice C is wrong because therapeutic effects are equivalent. Choice D is incorrect since only inactive ingredients differ.
Drugs that are affected by genetic polymorphisms of UGT1A1 include:
- A. Warfarin
- B. Irinotecan
- C. Acetaminophen
- D. All of the above
Correct Answer: B
Rationale: Choice B is correct because irinotecan's active metabolite is glucuronidated by UGT1A1; poor function increases toxicity, requiring genetic consideration. Choice A is incorrect as warfarin's metabolism is via CYP2C9, not UGT1A1. Choice C is wrong because acetaminophen uses other UGT enzymes, not specifically UGT1A1 critically. Choice D is incorrect since only irinotecan is notably affected by UGT1A1 polymorphisms.
Pharmacokinetic changes in the elderly that affect drug dosing include:
- A. Decreased renal function
- B. Increased liver metabolism
- C. Decreased body fat
- D. All of the above
Correct Answer: A
Rationale: Choice A is correct because decreased renal function in the elderly slows drug excretion, requiring dose adjustments to prevent accumulation, per geriatric pharmacology. Choice B is incorrect as liver metabolism decreases, not increases. Choice C is wrong because body fat increases, not decreases. Choice D is incorrect since only A is accurate.
A woman who is pregnant tells an NP that she has been taking sertraline for depression for several years but is worried about the effects of this drug on her fetus. The NP will consult with this patient's psychiatrist and will recommend that she:
- A. stop taking the sertraline now.
- B. continue taking the antidepressant.
- C. change to a different antidepressant.
- D. taper off the sertraline gradually.
Correct Answer: B
Rationale: The correct answer is B because continuing sertraline is often safer than untreated depression, with psychiatric consultation. Choice A is incorrect (abrupt stopping risky). Choice C is wrong (changing not first step). Choice D is inaccurate (tapering not indicated without specialist input).