Which of the following drugs is a leucotreine D4 receptor (LTD4) blocker?

Correct Answer: C

Rationale: The correct answer is C: Zafirlukast (Accolate). Zafirlukast is a leukotriene receptor antagonist that specifically blocks the action of leukotriene D4 (LTD4) at its receptor. This drug helps in reducing inflammation in conditions like asthma by blocking the effects of LTD4. Ibuprofen (A) and Diclofenac (D) are nonsteroidal anti-inflammatory drugs (NSAIDs) that work by inhibiting cyclooxygenase enzymes. Zileuton (B) is a 5-lipoxygenase inhibitor that blocks the formation of leukotrienes but does not specifically target the LTD4 receptor. Therefore, the correct choice is C as it directly blocks the LTD4 receptor, unlike the other options.

Correct Answer: B

Rationale: Step-by-step rationale for why choice B (Vitamin PP) is correct: 1. Vitamin PP is not a vitamin-like compound. 2. Vitamin PP refers to niacin (B3), which is essential and classified as a vitamin. 3. Choline, Vitamin U, and Orotate acid are vitamin-like compounds. 4. Choline is essential for liver function. 5. Vitamin U aids in digestive health. 6. Orotate acid is involved in nucleic acid metabolism. Summary of why other choices are incorrect: - Choice A (Choline): Essential for liver function. - Choice C (Vitamin U): Aids in digestive health. - Choice D (Orotate acid): Involved in nucleic acid metabolism.

Correct Answer: A

Rationale: Correct Answer: A (TRUE) Rationale: 1. Drugs and diet independently lower blood cholesterol levels. 2. When used together, their effects are additive, leading to a greater reduction. 3. This synergy implies that the statement is true. 4. Other options (B, C, D) are incorrect as they do not acknowledge the additive nature of combining drugs and diet interventions.

Correct Answer: D

Rationale: The correct answer is D: Metastatic calcifications. Cholecalciferol, a form of vitamin D, can lead to excessive calcium levels in the blood, causing calcium deposits in soft tissues like the kidneys, lungs, and blood vessels. This can result in metastatic calcifications. Choice A is incorrect as cholecalciferol deficiency, not excess, leads to defective bone mineralization. Choice B is unrelated to cholecalciferol effects. Choice C is not a common side effect of cholecalciferol supplementation.

Correct Answer: A

Rationale: The correct answer is A: Furosemide (Lasix). Furosemide is a loop diuretic that acts on the ascending loop of Henle to inhibit sodium reabsorption, leading to sodium loss. In patients with low glomerular filtration rates, furosemide can still promote sodium loss by directly affecting renal tubular function. Acetazolamide, on the other hand, is a carbonic anhydrase inhibitor that primarily works in the proximal tubule and is not as effective in promoting sodium loss in patients with low GFR. Therefore, the correct choice is A as furosemide can promote sodium loss in patients with low GFR, while acetazolamide is not as effective in this scenario.