Which of the following statements is correct for clozapine?

Correct Answer: A

Rationale: Rationale: A: Correct. Clozapine has potent anticholinergic activity, leading to side effects like dry mouth and constipation. B: Incorrect. Clozapine has higher affinity for serotonin receptors than D1 and D2 dopamine receptors. C: Incorrect. Clozapine is known for low extrapyramidal side effects compared to typical antipsychotics. D: Incorrect. Clozapine is an atypical antipsychotic, not related to typical antipsychotic agents.

Correct Answer: A

Rationale: Rationale: 1. Buspirone is a non-benzodiazepine anxiolytic that acts on serotonin receptors, not GABA receptors like other sedative-hypnotic drugs. 2. Since it does not target GABA receptors, it does not potentiate CNS depressant effects of ethanol, phenothiazines, or tricyclic antidepressants. 3. This makes it the only drug in the list that does not interact with these substances, making it the correct answer. Summary: - Phenobarbital, Diazepam, and Chloralhydrate are sedative-hypnotic drugs that potentiate CNS depressant effects of ethanol and other drugs due to their action on GABA receptors. - Buspirone, on the other hand, does not potentiate these effects as it acts on serotonin receptors, not GABA receptors.

Correct Answer: A

Rationale: Rationale: Sevoflurane decreases the ventilatory response to hypoxia by depressing the central nervous system. It inhibits the brain's response to low oxygen levels, leading to decreased breathing effort. Nitrous oxide, desflurane, and halothane do not have the same effect on the ventilatory response to hypoxia. Nitrous oxide actually stimulates the ventilatory response, while desflurane and halothane may have minimal effects or slightly increase the response. Thus, Sevoflurane is the correct choice as it specifically decreases the ventilatory response to hypoxia.

Correct Answer: B

Rationale: The correct answer is B: Sucralfate. Sucralfate forms a physical barrier by binding to the ulcer site, protecting it from stomach acid and pepsin. Ranitidine (A) and Omeprazole (C) are both acid-reducing drugs that work by inhibiting acid production. Pirenzepine (D) is a muscarinic receptor antagonist that decreases acid secretion but does not form a physical barrier. Therefore, Sucralfate is the correct choice for forming a physical barrier to HCl and pepsin.

Correct Answer: B

Rationale: The correct answer is B because aspirin inhibits cyclooxygenase (COX) enzyme, which is responsible for thromboxane synthesis. Thromboxane promotes platelet aggregation and vasoconstriction. By inhibiting thromboxane synthesis, aspirin reduces platelet aggregation, making it an effective antiplatelet agent. Choice A is incorrect because plasminogen is not involved in the mechanism of aspirin action. Choice C is incorrect because it describes the mechanism of heparin, not aspirin. Choice D is incorrect because inhibiting the glycoprotein IIb/IIIa complex is the mechanism of action of drugs like abciximab, not aspirin.