Probucol (Lorelco) reduces the risk of atherosclerosis by stimulating the rate of clearance of LDL by receptor-mediated pathways. This consideration is:

Correct Answer: B

Rationale: Rationale: 1. Probucol does not stimulate the rate of clearance of LDL by receptor-mediated pathways. 2. Probucol works by increasing HDL levels and reducing LDL oxidation. 3. Therefore, the statement that Probucol stimulates LDL clearance is false. 4. Choice B is correct as it accurately reflects the mechanism of action of Probucol. Summary: - Choice A is incorrect as Probucol does not stimulate LDL clearance. - Choice C is incorrect as not all statements are true. - Choice D is incorrect as the statement is false.

Correct Answer: A

Rationale: Step-by-step rationale for why choice A (Hydrochlorothiazide) is correct: 1. Hydrochlorothiazide is a thiazide diuretic that decreases urine volume by increasing water reabsorption. 2. In nephrogenic diabetes insipidus, the kidneys are unable to respond to antidiuretic hormone (ADH), causing excessive urine production. 3. Hydrochlorothiazide can help reduce urine output by enhancing water reabsorption, thus alleviating symptoms of nephrogenic diabetes insipidus. Summary of other choices: - Choice B (Amiloride) is a potassium-sparing diuretic that does not directly address the underlying mechanism of nephrogenic diabetes insipidus. - Choice C (Both of the above) is incorrect as only Hydrochlorothiazide is indicated for treating nephrogenic diabetes insipidus. - Choice D (Neither of the above) is incorrect as Hydrochlorothiazide is indeed

Correct Answer: B

Rationale: The correct answer is B: Polymyxins. Polymyxins are antibiotics that work by altering the permeability of the bacterial cell membrane, leading to leakage of cellular contents and ultimately bacterial cell death. This mechanism of action is specific to polymyxins, making it the correct choice. Incorrect Choices: A: Glycopeptides - Glycopeptides work by inhibiting cell wall synthesis, not by altering cell membrane permeability. C: Tetracyclines - Tetracyclines inhibit protein synthesis in bacteria, they do not target cell membrane permeability. D: Cephalosporins - Cephalosporins interfere with cell wall synthesis, they do not directly affect cell membrane permeability.

Correct Answer: C

Rationale: Step-by-step rationale for choice C: 1. Ethambutol is known to cause retrobulbar neuritis, a condition that affects the optic nerve leading to vision changes. 2. The specific symptom of red-green color blindness is commonly associated with ethambutol toxicity. 3. This effect is due to the drug's direct impact on the optic nerve. 4. Regular monitoring of visual acuity and color vision is recommended during ethambutol treatment. Summary of other choices: A. Cardiotoxicity: Ethambutol is not known to cause direct cardiotoxic effects. B. Immunetoxicity: Ethambutol primarily affects the optic nerve, not the immune system. D. Hepatotoxicity: Ethambutol is generally well-tolerated by the liver and does not commonly cause hepatotoxicity.

Correct Answer: D

Rationale: The correct answer is D: Ivermectin. Ivermectin is the drug of choice for strongyloidiasis due to its high efficacy and low toxicity. It works by paralyzing and killing the parasites. Niclosamide (A) is used for tapeworm infections, Praziquantel (B) for schistosomiasis, and Bithionol (C) for fascioliasis. Therefore, D is the correct choice for treating strongyloidiasis.