Propranolol has all of the following cardiovascular effects EXCEPT:

Correct Answer: B

Rationale: The correct answer is B because propranolol does not reduce blood flow to the brain. Propranolol is a non-selective beta-blocker that decreases cardiac work and oxygen demand (choice A), inhibits renin secretion (choice C), and increases the atrioventricular nodal refractory period (choice D). By blocking beta receptors in the heart and blood vessels, propranolol reduces heart rate, contractility, and blood pressure, leading to decreased oxygen demand. Inhibiting renin secretion helps lower blood pressure. Increasing the atrioventricular nodal refractory period can slow down the conduction of electrical impulses in the heart, helping to control heart rhythm. Therefore, choices A, C, and D are all accurate effects of propranolol on the cardiovascular system.

Correct Answer: D

Rationale: The correct answer is D, All of the above. Phenytoin, Valproate, and Topiramate are known to have teratogenic effects. Phenytoin can cause fetal hydantoin syndrome, Valproate is associated with neural tube defects, and Topiramate can lead to cleft lip and palate. These antiseizure drugs should be used cautiously in pregnant women due to the potential harm to the developing fetus. The other choices are incorrect because only Phenytoin, Valproate, and Topiramate are specifically linked to teratogenicity.

Correct Answer: C

Rationale: Rationale: 1. Kappa and delta agonists inhibit postsynaptic neurons by opening K+ channels. 2. They also close voltage-gated Ca2+ channels on presynaptic nerve terminals. 3. Therefore, choice C (Both a and b) is correct, as it encompasses both actions. Summary: - Choice A is incorrect because it only mentions the action of opening K+ channels. - Choice B is incorrect as it only refers to closing voltage-gated Ca2+ channels. - Choice D is unrelated to the actions of kappa and delta agonists on neuronal transmission.

Correct Answer: B

Rationale: The correct answer is B: Antipyretic effect. Non-narcotic agents, such as NSAIDs, have antipyretic properties, helping to reduce fever by acting on the hypothalamus. This is achieved without causing respiratory depression (A), euphoria (C), or physical dependence (D). NSAIDs work by inhibiting prostaglandin synthesis, which helps in reducing inflammation, pain, and fever without affecting the respiratory center or causing addictive tendencies. Thus, option B is the correct choice based on the pharmacological actions of non-narcotic agents.

Correct Answer: B

Rationale: Lithium carbonate is commonly used to treat bipolar disorder due to its mood-stabilizing effects. It helps regulate neurotransmitters in the brain, specifically serotonin and norepinephrine, which are implicated in mood regulation. For petit mal seizures, anti-epileptic drugs like ethosuximide are typically prescribed. Neurosis is treated through psychotherapy and medication targeting specific symptoms. Trigeminal neuralgia is usually managed with anticonvulsants like carbamazepine. In summary, lithium carbonate's mechanism of action aligns with the treatment goals of bipolar disorder, making it the correct choice.