Ketoprofen is a propionic acid derivative that inhibits both cyclooxygenase (nonselectively) and lipoxygenase. This statement is:

Correct Answer: A

Rationale: The correct answer is A: TRUE. Ketoprofen is indeed a propionic acid derivative that inhibits both cyclooxygenase and lipoxygenase nonselectively. This is because ketoprofen belongs to the class of nonsteroidal anti-inflammatory drugs (NSAIDs), which work by inhibiting cyclooxygenase enzymes to reduce inflammation and pain. Additionally, ketoprofen has been shown to inhibit lipoxygenase, another enzyme involved in the inflammatory process. Therefore, this statement accurately describes the pharmacological actions of ketoprofen. Choices B and C are incorrect because the statement is true, and choice D is incorrect as it suggests all options are correct when only option A is accurate in this case.

Correct Answer: D

Rationale: The correct answer is D - All of the above. Cholestyramine binds bile acids, leading to malabsorption of fat-soluble vitamins like vitamin K. Coumarins inhibit the recycling of vitamin K epoxide, reducing its availability. Certain antibiotics disrupt gut flora, affecting vitamin K production. Therefore, all choices prevent vitamin K from exerting its metabolic effects.

Correct Answer: A

Rationale: The correct answer is A because drug combinations are likely synergistic when they target different steps in the same pathway, resulting in additive or synergistic effects. This increases efficacy and reduces side effects. Choice B is incorrect as the statement is true. Choices C and D are incorrect as they are not valid options in this context.

Correct Answer: D

Rationale: The correct answer is D because cholecalciferol, also known as vitamin D3, exerts its effects through genomic effects (regulating gene expression) and cytoplasmic effects (regulating calcium transport). This is crucial for its role in calcium homeostasis and bone health. A is incorrect because cholecalciferol is typically administered orally and does not require frequent monitoring of calcium and phosphorus serum levels. B is incorrect because cholecalciferol promotes bone formation by enhancing osteoblast activity, not inhibiting osteoclasts. C is incorrect because cholecalciferol actually helps increase serum calcium levels by enhancing calcium absorption in the intestines and promoting calcium reabsorption in the kidneys, rather than lowering them.

Correct Answer: C

Rationale: Sustained use of furosemide and acetazolamide can lead to increased plasma urate concentrations. Furosemide inhibits uric acid secretion, while acetazolamide impairs renal excretion of uric acid. Therefore, both drugs can result in elevated plasma urate levels. Choice C is correct. Choice A is incorrect because furosemide does not decrease plasma urate concentrations. Choice B is incorrect because acetazolamide does not lower plasma urate concentrations. Choice D is incorrect as both drugs can increase plasma urate levels.