Which of the following medications is used to reduce the risk of stroke in patients with atrial fibrillation?

Correct Answer: C

Rationale: The correct answer is C: Warfarin. Warfarin is an anticoagulant that helps prevent blood clots, reducing the risk of stroke in patients with atrial fibrillation. It is more effective than aspirin or clopidogrel in preventing stroke in this patient population. Heparin is not typically used for long-term stroke prevention in atrial fibrillation.

Correct Answer: B

Rationale: The correct answer is B: Osteoporosis. Corticosteroid therapy can lead to decreased bone density over time, resulting in osteoporosis. This occurs due to the suppression of bone formation and increased bone resorption. Hypotension (choice A) is not a common side effect of corticosteroid therapy; rather, it can cause fluid retention and hypertension. Tachycardia (choice C) is also not a typical side effect of corticosteroids; instead, they may cause bradycardia. Hyperkalemia (choice D) is not directly associated with corticosteroid therapy; in fact, corticosteroids can lead to hypokalemia due to potassium loss.

Correct Answer: B

Rationale: The correct answer is B: Improving insulin sensitivity in peripheral tissues. Metformin helps improve insulin sensitivity by increasing the uptake of glucose by muscle and fat cells, reducing glucose production in the liver, and decreasing insulin resistance. This leads to better control of blood glucose levels in individuals with type 2 diabetes. Choice A is incorrect because metformin does not directly increase insulin secretion from the pancreas. Choice C is incorrect because metformin does not inhibit glucose absorption in the intestines. Choice D is incorrect because although metformin may increase renal glucose excretion to some extent, its primary mechanism of action is improving insulin sensitivity in peripheral tissues.

Correct Answer: B

Rationale: The correct answer is B: Inhibiting HMG-CoA reductase in the liver. Rosuvastatin is a statin medication that works by inhibiting the enzyme HMG-CoA reductase, which is responsible for the production of cholesterol in the liver. By inhibiting this enzyme, rosuvastatin helps lower the levels of LDL cholesterol in the blood. Choices A, C, and D are incorrect because rosuvastatin does not act by inhibiting cholesterol reabsorption in the intestines, increasing HDL cholesterol levels, or increasing the excretion of cholesterol in the bile.

Correct Answer: A

Rationale: The correct answer is A: Muscle pain. Statin drugs are known to cause myopathy, which can manifest as muscle pain, weakness, or tenderness. This adverse effect is due to statins affecting muscle cells and potentially leading to muscle inflammation or damage. Headache (B), weight gain (C), and coughing (D) are not common adverse effects associated with statin drugs. Muscle pain is a well-documented and frequently reported side effect, making it the correct choice in this scenario.