The mechanism of haloperidol antipsychotic action is:

Correct Answer: A

Rationale: The correct answer is A: Blocking D2 receptors. Haloperidol is a typical antipsychotic that primarily works by blocking dopamine D2 receptors in the brain, leading to a reduction in dopamine activity and alleviating psychotic symptoms. Choices B and C are incorrect as haloperidol does not primarily act by central alpha-adrenergic blocking or inhibition of norepinephrine uptake mechanisms. Choice D, "All of the above," is incorrect as haloperidol's main mechanism of action is through D2 receptor blockade, not through all the mechanisms listed.

Correct Answer: C

Rationale: Rationale for correct answer (C): 1. Buspirone is a serotonin receptor agonist and does not directly interact with the GABAergic system. 2. Buspirone is not associated with marked hypnotic, anticonvulsant, or muscle relaxant properties. 3. Studies show that buspirone causes less psychomotor impairment and does not affect driving skills. 4. Therefore, choice C is correct as it accurately contrasts buspirone from benzodiazepines. Summary of incorrect choices: A. Benzodiazepines interact with the GABAergic system, not buspirone. B. Benzodiazepines have hypnotic, anticonvulsant, and muscle relaxant properties, not buspirone. D. Buspirone has minimal abuse liability compared to benzodiazepines, which have high abuse potential.

Correct Answer: A

Rationale: Desflurane is the correct answer because it causes sympathetic activation by stimulating the central nervous system, leading to increased blood pressure and heart rate. Desflurane has a high potency in activating sympathetic responses compared to the other options. Sevoflurane and isoflurane have minimal impact on sympathetic activation. Nitrous oxide primarily acts as a weak anesthetic and does not cause significant sympathetic stimulation.

Correct Answer: B

Rationale: The correct answer is B: FALSE. Cimetidine is a known inhibitor of hepatic drug metabolism, specifically through inhibition of CYP enzymes. This leads to increased levels of certain drugs in the body. Choice A is incorrect because cimetidine does have an effect on hepatic drug metabolism. Choice C is also incorrect as it implies that all statements are true, which is not the case. Choice D is incorrect as well, as the statement is indeed false.

Correct Answer: A

Rationale: The correct answer is A: TRUE. Heparin is recommended for the treatment of deep venous thrombosis (DVT) because it prevents further clot formation and helps dissolve existing clots. Heparin works by inhibiting the formation of blood clots. Other choices (B, C, D) are incorrect because they do not align with the established medical guidelines for DVT treatment.