Correct Answer: B

Rationale:
Choice B is correct because CYP2D6 ultrarapid metabolizers convert codeine to morphine too quickly, risking overdose and toxicity, so it should be avoided.
Choice A is incorrect as acetaminophen's metabolism isn't significantly CYP2D6-dependent, posing less risk.
Choice C is wrong because ibuprofen isn't metabolized by CYP2D6, so ultrarapid status is irrelevant.
Choice D is incorrect since only codeine poses a specific danger here.

Correct Answer: B

Rationale:
Choice B is correct because ketamine is a Schedule III drug with moderate abuse potential and medical use (anesthetic), per DEA.
Choice A is incorrect as oxycodone is Schedule II.
Choice C is wrong because lorazepam is Schedule IV.
Choice D is incorrect since only ketamine fits.

Correct Answer: D

Rationale:
Choice D is correct because Lexicomp offers dosing, Medline provides studies, and Beers Criteria lists risky drugs—all key for elderly prescribing.
Choice A is incorrect alone as it's one tool.
Choice B is wrong by itself because it's research-focused.
Choice C is incorrect solo since Beers is specific.

Correct Answer: D

Rationale:
Choice D is correct because tapering (reduces shock), supportive care (e.g., hydration), and medications (e.g., methadone for opioids) all manage withdrawal, per treatment protocols.
Choice A is incorrect alone as it's one method.
Choice B is wrong by itself because care is just part.
Choice C is incorrect solo since meds are only one option.

Correct Answer: B

Rationale:
Choice B is correct because St John's wort induces CYP3A4 and affects serotonin, risking reduced antidepressant efficacy or serotonin syndrome, so it's to be avoided.
Choice A is incorrect as ginkgo biloba doesn't significantly interact with antidepressants.
Choice C is wrong because valerian root's sedative effect is minor and not a major concern.
Choice D is incorrect since only St John's wort poses a substantial risk.