Which of the following drugs is most commonly used for causing a noxious reaction to alcohol by blocking its metabolism?

Correct Answer: B

Rationale: The correct answer is B: Disulfiram. Disulfiram inhibits the enzyme aldehyde dehydrogenase, leading to accumulation of acetaldehyde when alcohol is consumed. This causes a noxious reaction (e.g., nausea, vomiting) as acetaldehyde builds up. Naltrexone (A) is an alcohol antagonist that reduces alcohol cravings. Diazepam (C) is a benzodiazepine used for anxiety and alcohol withdrawal symptoms. Morphine (D) is an opioid analgesic and not used for causing a noxious reaction to alcohol.

Correct Answer: C

Rationale: The correct answer is C: Fluoxetine. Fluoxetine is a phenyltolylpropylamine derivative due to its chemical structure. It falls under the class of selective serotonin reuptake inhibitors (SSRIs), making it an antidepressant agent. Paroxetine (A) is an SSRI but not a phenyltolylpropylamine derivative. Maprotiline (B) is a tetracyclic antidepressant, not a phenyltolylpropylamine derivative. Amitriptyline (D) is a tricyclic antidepressant, not a phenyltolylpropylamine derivative. Therefore, the correct answer is C.

Correct Answer: D

Rationale: The correct answer is D: Prazepam. Prazepam is preferred for elderly patients due to its long half-life, which reduces the risk of accumulation and potential side effects. Clorazepate (A) and Clordiazepoxide (B) have active metabolites that may accumulate in the elderly. Triazolam (C) has a short half-life, leading to potential next-day sedation. Therefore, Prazepam is the safest choice for elderly patients.

Correct Answer: C

Rationale: Step-by-step rationale for why Ketamine (choice C) is the correct answer: 1. Ketamine is a known NMDA receptor antagonist, blocking the receptor's activity. 2. By inhibiting NMDA receptors, Ketamine produces dissociative anesthesia. 3. Thiopental (A) is a GABA agonist, Halothane (B) is a volatile anesthetic, and Sevoflurane (D) enhances GABA activity, not acting on NMDA receptors.

Correct Answer: A

Rationale: Step-by-step rationale: 1. Zafirlukast is a leukotriene receptor antagonist used to treat asthma. 2. Aspirin-sensitive asthma is a condition triggered by aspirin and other NSAIDs. 3. Studies have shown that zafirlukast can prevent bronchoconstriction in aspirin-sensitive asthma. 4. Therefore, the statement that Zafirlukast prevents aspirin-sensitive asthma is TRUE. Summary: - Choice A is correct because zafirlukast has been proven to prevent aspirin-sensitive asthma. - Choice B is incorrect as evidence supports the effectiveness of zafirlukast. - Choice C is incorrect as not all choices are true. - Choice D is incorrect as the correct answer is A, making this choice incorrect.