Which of the following antihypertensive agents should be avoided in elderly patients?

Correct Answer: B

Rationale: In the context of CNS pharmacology and the treatment of hypertension in elderly patients, the correct answer is B) Methyldopa 250 mg three times a day. Methyldopa is a centrally acting alpha-2 adrenergic agonist that is commonly used as an antihypertensive agent in elderly patients due to its favorable side effect profile and proven efficacy in this population. A) Amlodipine is a calcium channel blocker that is generally well-tolerated in elderly patients and is commonly used in this population for the management of hypertension. However, it is not the best choice to avoid in elderly patients. C) Benazepril is an ACE inhibitor that can also be safely used in elderly patients for the treatment of hypertension. It is not specifically contraindicated in this population. D) Hydrochlorothiazide is a thiazide diuretic that is commonly prescribed for hypertension. While it is generally well-tolerated, it may not be the first choice in elderly patients due to the potential risk of electrolyte imbalances and adverse effects on renal function. In an educational context, it is important for healthcare providers to consider the unique characteristics of elderly patients when selecting antihypertensive agents. Methyldopa is often preferred in this population due to its proven efficacy, tolerability, and lower risk of adverse effects compared to other agents. Understanding the pharmacological properties and considerations for each antihypertensive drug is crucial for providing safe and effective care to elderly patients with hypertension.

Correct Answer: D

Rationale: In this scenario, parenteral calcium serves as an antidote for both verapamil overdoses and hyperkalemia. Parenteral calcium is effective in verapamil overdoses because verapamil is a calcium channel blocker that can lead to severe cardiovascular toxicity, including bradycardia and hypotension. Calcium acts to antagonize the effects of verapamil and restore cardiac contractility. Hyperkalemia, characterized by elevated potassium levels, can cause dangerous cardiac arrhythmias. Calcium administration in hyperkalemia helps stabilize the cardiac cell membrane potential by counteracting the depolarizing effect of high potassium levels. Regarding the incorrect options: - Verapamil overdoses alone do not warrant parenteral calcium as the sole antidote. Other interventions like supportive care, activated charcoal, and possibly vasopressors may be needed. - Cocaine intoxication is not treated with parenteral calcium. Management focuses on supportive measures, benzodiazepines for agitation, and potentially vasopressors for severe cases. In an educational context, understanding the specific antidotes for different toxicological situations is crucial for healthcare providers, especially those working in emergency settings. This knowledge can be life-saving in managing overdoses and toxicities effectively. It reinforces the importance of accurate and timely interventions based on the underlying pharmacological mechanisms at play.

Correct Answer: D

Rationale: The correct therapeutic range for lithium in the treatment of acute mania is option D) 0.8-1.2 mEq/L. This range is considered appropriate for managing acute manic episodes effectively while minimizing the risk of toxicity. Option A) 0.6-1.0 mEq/L is too low to achieve optimal therapeutic effects in acute mania. Option B) 0.6-1.5 mEq/L includes a range that exceeds the upper limit for safety, increasing the risk of adverse effects. Option C) 0.6-0.8 mEq/L is below the recommended therapeutic range and may not provide adequate control of manic symptoms. In an educational context, understanding the appropriate therapeutic range for lithium is crucial for healthcare professionals treating patients with bipolar disorder. Maintaining lithium levels within the therapeutic range is essential for achieving optimal clinical outcomes while minimizing the risk of adverse effects. Educating healthcare providers on accurate dosing and monitoring of lithium levels can improve patient safety and treatment efficacy in managing bipolar disorder.

Correct Answer: B

Rationale: In this CNS Pharmacology Drug Quiz question, the correct answer is B) Mercury. BAL (British Anti-Lewisite) is a chelating agent used to counteract the toxic effects of heavy metal poisoning, particularly mercury. Mercury poisoning can occur through ingestion, inhalation, or skin contact with mercury compounds. BAL works by forming a complex with the mercury ions, which can then be excreted from the body, reducing the toxic effects of mercury. Option A) Atropine is a muscarinic antagonist used to treat symptoms of organophosphate poisoning by blocking excessive stimulation of acetylcholine receptors. Options C) Morphine and D) Barbiturates are not typically associated with BAL usage or the treatment of heavy metal poisoning. Understanding the specific antidotes for different types of poisonings is crucial in clinical practice to provide timely and effective interventions. Pharmacology quizzes like this help reinforce knowledge about drug actions, indications, and contraindications, enhancing critical thinking skills for healthcare professionals managing poisoning cases.

Correct Answer: C

Rationale: Phencyclidine (PCP) is a non-competitive antagonist of N-methyl-D-aspartate (NMDA) receptors. NMDA receptors play a crucial role in synaptic plasticity, learning, and memory. By blocking these receptors, PCP disrupts normal glutamatergic neurotransmission, leading to its dissociative effects. Option A) Kainate receptors and Option B) AMPA receptors are not the target receptors of PCP. Kainate and AMPA receptors are ionotropic glutamate receptors, but they are not affected by PCP in the same way as NMDA receptors. Option D) "All of the above" is incorrect because PCP specifically targets NMDA receptors and does not have a significant effect on kainate or AMPA receptors. Understanding the pharmacology of CNS drugs, like PCP, is essential for healthcare professionals to make informed decisions about their use, potential side effects, and interactions with other medications. Knowledge of drug mechanisms helps in making appropriate therapeutic choices and managing patient care effectively.