Principal aim for treatment of Parkinsonian disorders is:

Correct Answer: B

Rationale: The correct answer is B because the principal aim for treating Parkinsonian disorders is to restore dopaminergic activity with levodopa and dopamine agonists. This is because Parkinson's disease is primarily caused by a deficit of dopamine in the brain. Levodopa is converted to dopamine in the brain, helping to alleviate symptoms. Choice A is incorrect because antimuscarinic drugs target the cholinergic system, not the dopaminergic system, and are not the primary treatment for Parkinson's disease. Choice C is incorrect because glutamate antagonists target a different neurotransmitter system and are not the mainstay of treatment for Parkinson's disease. Choice D is incorrect because while restoring balance between cholinergic and dopaminergic influences may be important, the primary aim is to address the dopaminergic deficit.

Correct Answer: C

Rationale: The correct answer is C because ketorolac is a nonsteroidal anti-inflammatory drug (NSAID) that does not have a high potential for physical dependence and abuse like opioids. A: It inhibits COX, reducing inflammation and pain. B: It is effective for short-term pain relief but is not as potent as morphine. D: It does not produce respiratory depression, which is a common side effect of opioids. In summary, C is incorrect as ketorolac is not associated with physical dependence and abuse, making it a safer option compared to opioids for pain management.

Correct Answer: C

Rationale: The correct answer is C: Tranylcypramine. Tranylcypramine is a nonhydrazide derivative of MAO inhibitor that has amphetamine-like activity due to its structural similarity to amphetamines. Phenelzine and Moclobemide are not related to nonhydrazide derivatives and do not exhibit amphetamine-like activity. Therefore, the correct choice is C.

Correct Answer: C

Rationale: The correct answer is C: Hypotension. Caffeine is a stimulant that can increase blood pressure, so hypotension is not an adverse effect. A: Arrhythmias can occur due to caffeine's stimulant effects on the heart. B: Insomnia is a common side effect of caffeine due to its ability to disrupt sleep patterns. D: Psychomotor excitation can happen as caffeine increases alertness and arousal. Therefore, hypotension is the exception among the choices as it does not align with caffeine's typical effects on the body.

Correct Answer: B

Rationale: The correct answer is B: 7-10 days. Opioid withdrawal symptoms typically start within 6-12 hours after the last dose and peak around 2-3 days. The acute phase, marked by intense symptoms like anxiety, sweating, and insomnia, usually lasts about a week. After this period, symptoms gradually improve. Choices A, C, and D are incorrect. Choice A is too short for the acute phase. Choice C is too long, indicating the more prolonged post-acute withdrawal phase. Choice D is significantly longer and indicative of a chronic condition, not acute withdrawal.