Which of the following hypnotic agents is absorbed slowly?

Correct Answer: A

Rationale: Phenobarbital is absorbed slowly due to its high lipid solubility, leading to a delayed onset of action. It has a long half-life and is metabolized in the liver. Flurazepam, Triazolam, and Temazepam are absorbed more rapidly and have shorter durations of action compared to Phenobarbital. Flurazepam is a long-acting benzodiazepine, while Triazolam and Temazepam have intermediate durations of action. Therefore, the correct answer is A (Phenobarbital) because of its slow absorption compared to the other choices.

Correct Answer: D

Rationale: Rationale: 1. Carbidopa inhibits the peripheral metabolism of levodopa, leading to increased levodopa blood levels and prolonged half-life. 2. By enhancing levodopa bioavailability, carbidopa allows for a significant reduction in levodopa dose, minimizing toxic effects. 3. Carbidopa also reduces the latency period before beneficial effects occur. Therefore, the correct answer is D, as all statements are true and supported by pharmacological principles. Other choices are incorrect as they do not encompass the comprehensive effects of combining carbidopa and levodopa.

Correct Answer: B

Rationale: The correct answer is B: Coma, depressed respiration, and miosis. In opioid overdosage, coma occurs due to central nervous system depression, depressed respiration is a result of respiratory center suppression, and miosis is a classic sign of opioid toxicity due to the activation of the parasympathetic nervous system. Mydriasis (pupil dilation) is not a common feature in opioid overdosage. Chills and abdominal cramps are more indicative of opioid withdrawal rather than overdose. Tremor and vomiting are not typically part of the diagnostic triad of opioid overdosage.

Correct Answer: A

Rationale: The correct answer is A: The nigrostriatal system. Parkinsonian symptoms and tardive dyskinesia are caused by dopamine blockade in the nigrostriatal system, which is responsible for motor control. Dopamine blockade here leads to movement disorders. Choices B, C, and D are incorrect because tardive dyskinesia and Parkinsonian symptoms are not primarily related to dopamine blockade in the mesolimbic and mesofrontal systems (B), chemoreceptor trigger zone of the medulla (C), or the tuberoinfundibular system (D). These systems are associated with other functions such as reward processing, nausea/vomiting regulation, and hormone release, respectively.

Correct Answer: B

Rationale: The correct answer is B (2-3 weeks) because antidepressants typically require time to build up in the body and affect neurotransmitter levels. It takes time for the brain to adapt to the medication and for changes in mood to become noticeable. A: 2-3 days is too short for significant effects. C: 24 hours is not enough time for the medication to take full effect. D: 2-3 months is too long for most individuals to wait for improvement.