Characteristics of methoxamine include all of the following EXCEPT:

Correct Answer: B

Rationale: The correct answer is B because methoxamine is a direct-acting alpha1-receptor agonist that increases blood pressure by causing vasoconstriction and increasing total peripheral resistance. It does not increase heart rate, contractility, or cardiac output; instead, it can cause reflex bradycardia due to its hypertensive effect. Therefore, the statement that it increases heart rate, contractility, and cardiac output is incorrect. The other choices (A, C, and D) are all characteristics of methoxamine, making them incorrect options for this question.

Correct Answer: A

Rationale: The correct answer is A: REM sleep. During REM (rapid eye movement) sleep, brain activity is high and resembles waking patterns. This stage is associated with vivid dreams. Slow wave sleep (choice B) is deep, restorative sleep with minimal dreaming. Stage 2 NREM sleep (choice C) is a lighter sleep stage with occasional light dreaming. Option D is incorrect because only REM sleep is widely recognized as the stage most responsible for dreaming due to increased brain activity and vivid dreams.

Correct Answer: B

Rationale: Step-by-step rationale: 1. Diazepam is a benzodiazepine that enhances GABAergic transmission by binding to GABA-A receptors. 2. GABA-A receptors are chloride channels that open in response to GABA binding. 3. By binding to GABA-A receptors, diazepam increases chloride influx, leading to neuronal hyperpolarization and inhibition of seizure activity. Summary: A. Vigabatrin inhibits GABA transaminase, increasing GABA levels indirectly. C. Gabapentin modulates calcium channels and has no direct effect on GABA receptors. D. Valproate increases GABA levels but does not directly bind to GABA receptors.

Correct Answer: A

Rationale: The correct answer is A because mu (μ) receptors are primarily associated with analgesia, euphoria, respiratory depression, and physical dependence. This is supported by pharmacological studies and clinical observations. Choice B is incorrect because mydriasis and sedation are not typically associated with mu receptors. Choice C is incorrect because dysphoria, hallucinations, and respiratory/vasomotor stimulation are more commonly linked to other receptor types. Choice D is incorrect because respiratory stimulation is not a typical effect of mu receptor activation. Overall, the key characteristics of mu receptors align with the effects listed in option A, making it the correct choice.

Correct Answer: B

Rationale: Certainly! Fomepizol is the correct antidote for ethylene glycol and methanol poisoning as it inhibits the enzyme alcohol dehydrogenase, preventing the conversion of these toxic alcohols into their more harmful metabolites. Disulfiram (A) is used in alcohol aversion therapy, not for poisoning treatment. Naltrexone (C) is an opioid receptor antagonist used in alcohol dependence, not poisoning. Amphetamine (D) is a stimulant drug, not an antidote for poisoning. Thus, B is the correct choice for treating ethylene glycol and methanol poisonings.