Benzodiazepine′s usefulness is limited by:

Correct Answer: A

Rationale: The correct answer is A: Tolerance. Benzodiazepines are known to lead to tolerance, meaning that over time, the body requires higher doses to achieve the same effect. This limits their usefulness as long-term treatment options. Atropine-like symptoms (B) are not associated with benzodiazepines. Psychotic episodes (C) and myasthenic syndrome (D) are also not common side effects of benzodiazepines. Therefore, the correct answer is A as tolerance limits the effectiveness of benzodiazepines over time.

Correct Answer: C

Rationale: Certainly! The correct answer is C: Alcohol dehydrogenase. Fomepizole is used in treating methanol and ethylene glycol toxicity by inhibiting alcohol dehydrogenase, preventing the formation of toxic metabolites. This mechanism blocks the conversion of methanol and ethylene glycol into their toxic byproducts, formic acid, and glycolic acid, respectively. Choices A, B, and D are incorrect as fomepizole does not target aldehyde dehydrogenase, acetylcholinesterase, or monoamine oxidase in this context.

Correct Answer: C

Rationale: The correct answer is C: Clozapine. Clozapine is known for its high risk of potentially fatal agranulocytosis, a serious blood disorder. It also carries a risk of seizures at high doses. Haloperidol (A) is associated with extrapyramidal symptoms, not agranulocytosis or seizures. Risperidone (B) is less likely to cause agranulocytosis or seizures compared to clozapine. Chlorpromazine (D) can cause agranulocytosis but is not as well-known for this risk as clozapine.

Correct Answer: A

Rationale: The correct answer is A because actoprotectors are substances that improve physical efficiency by enhancing endurance, stamina, and overall physical performance. This is supported by scientific evidence showing their positive effects on exercise capacity and fatigue resistance. Choice B is incorrect because cognition enhancers focus on improving cognitive functions, not physical performance. Choice C is incorrect as actoprotectors do not raise non-specific resistance towards stresses but specifically target physical efficiency. Choice D is incorrect because actoprotectors do not directly stimulate respiratory and vasomotor centers in the brain, but rather enhance physical capabilities.

Correct Answer: B

Rationale: Buspirone has a slow onset of action due to its mechanism of action involving serotonin and dopamine receptors. This makes it unsuitable for acute anxiety or panic attacks. The slow onset allows for gradual anxiolytic effects over time. Other choices are incorrect because buspirone has a wide therapeutic index, minimal potential for physical dependence, and does not typically impair mentation or motor functions.