Which of the following opioid analgesics is used in combination with droperidol in neuroleptanalgesia?

Correct Answer: C

Rationale: The correct answer is C: Fentanyl. Fentanyl is used in combination with droperidol in neuroleptanalgesia due to its fast onset of action and potent analgesic effects, making it an ideal choice for sedation and analgesia during procedures. Morphine (choice A) is not typically used in neuroleptanalgesia due to its slower onset of action and shorter duration. Buprenorphine (choice B) is a partial opioid agonist and is not commonly used in neuroleptanalgesia. Lastly, the duplicate choice D (Morphine) is incorrect for the same reasons mentioned earlier. In summary, Fentanyl is the preferred choice for neuroleptanalgesia due to its rapid onset and potent analgesic properties compared to the other options.

Correct Answer: B

Rationale: The correct answer is B: Tranylcypramine. Tranylcypramine is an unselective MAO blocker, inhibiting both MAO-A and MAO-B, leading to long-lasting enzyme inhibition. Moclobemide (A) is a reversible MAO-A inhibitor. Selegiline (C) is a selective MAO-B inhibitor. Fluoxetine (D) is a selective serotonin reuptake inhibitor (SSRI) and does not inhibit MAO enzymes. Therefore, Tranylcypramine is the correct choice for producing long-lasting MAO inhibition.

Correct Answer: A

Rationale: The correct answer is A because caffeine actually stimulates gastric secretion, not inhibits it. Caffeine can increase stomach acid production, leading to potential digestive issues. Choices B, C, and D are incorrect because caffeine is known to cause hyperglycemia by increasing blood sugar levels, has a moderate diuretic action by increasing urine production, and increases free fatty acids in the bloodstream, which can affect metabolism. Therefore, based on its effects on gastric secretion, A is the correct answer.

Correct Answer: B

Rationale: The correct answer is B: More addictive and fast-acting. Heroin is derived from morphine and is more potent, leading to a faster onset of action and increased addictive potential. The rapid crossing of the blood-brain barrier contributes to its fast-acting properties. It is crucial to differentiate between heroin and morphine due to their varying addictive nature and speed of action. Choices A, C, and D are incorrect because heroin is not typically used clinically, is not more effective orally, and is actually more potent and faster-acting than morphine, making it not less potent and long-acting.

Correct Answer: B

Rationale: Step 1: Ketamine is the correct choice for dissociative anesthesia due to its unique mechanism of action, which involves blocking NMDA receptors, leading to dissociation of sensory input from conscious perception. Step 2: Midazolam (A) is a benzodiazepine used for sedation and anxiolysis, not dissociative anesthesia. Step 3: Fentanyl (C) is an opioid analgesic used for pain control, not dissociative anesthesia. Step 4: Thiopental (D) is a barbiturate used for induction of general anesthesia, not specifically for dissociative anesthesia.