Metoclopramide (Reglan) carries a black box warning that it can cause tardive dyskinesia with long-term therapy.

Correct Answer: A

Rationale: The correct answer is A (TRUE). Metoclopramide (Reglan) does carry a black box warning due to the risk of tardive dyskinesia with long-term use. Tardive dyskinesia is characterized by involuntary movements of the face and body and can be irreversible. The warning emphasizes the importance of using metoclopramide for the shortest duration possible to minimize this risk. The other choices (B, C, D) are incorrect because the black box warning for tardive dyskinesia associated with metoclopramide is a well-documented fact supported by clinical evidence and regulatory agencies.

Correct Answer: C

Rationale: The correct answer is C: NMDA receptor antagonist. Memantine is an NMDA receptor antagonist, which means it blocks the activity of NMDA receptors, specifically by binding to the receptor-operated cation channels and blocking the excessive influx of calcium ions. This mechanism helps regulate glutamate activity and prevents excitotoxicity. Choices A and B are incorrect because memantine is not related to GABA function or concentration. Choice D is incorrect as an NMDA receptor agonist would increase receptor activity, opposite to memantine's action.

Correct Answer: C

Rationale: The correct answer is C: Depression. SNRIs are commonly prescribed for depression as they work by increasing levels of serotonin and norepinephrine in the brain, which help regulate mood. In contrast, options A, B, and D are not typically indications for SNRIs. CHF (A) is treated with medications that help the heart function better, acute pancreatitis (B) is managed with pain control and supportive care, and autism (D) is managed with behavioral therapies and sometimes medications targeting specific symptoms. Hence, depression (C) is the most likely indication for SNRIs based on their mechanism of action and common therapeutic uses.

Correct Answer: A

Rationale: The correct answer is A because neuronal degeneration and decreased acetylcholine are key factors associated with the pathophysiology of Alzheimer's disease. Neuronal degeneration leads to cognitive decline, while decreased acetylcholine contributes to memory impairment. Incorrect Responses: B: Autoimmune changes in the myelin sheath are not typically associated with Alzheimer's disease, as it primarily involves neuronal degeneration. C: Beta-amyloid and neuritic plaques are characteristic pathological features of Alzheimer's disease, but they are not directly associated with the underlying pathophysiology. D: Neurofibrillary tangles and tau are also pathological hallmarks of Alzheimer's disease, but they are not the primary factors driving the disease process.

Correct Answer: B

Rationale: Step-by-step rationale for why choice B is correct: 1. Levodopa is the most effective medication for managing the motor symptoms of Parkinson's disease. 2. Carbidopa is often combined with Levodopa to enhance its effectiveness and reduce side effects. 3. The combination of Levodopa and Carbidopa is a standard and widely accepted treatment for Parkinson's disease. 4. Other choices are incorrect: A - Deep brain stimulation is not used to wean off patients from Levodopa; C - Amantadine is not typically used as a monotherapy for Parkinson's disease; D - Dopamine is not a medication but a neurotransmitter, and Levodopa is the preferred treatment over dopamine.