A nurse is caring for a client who has hypertension and nephropathy due to type 2 diabetes mellitus. The nurse should expect to administer which of the following medications to slow the progression of the nephropathy?

Choice A rationale Sitagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor, which works by increasing the levels of incretin hormones that stimulate insulin release and reduce glucagon secretion. While it is used to manage blood glucose in type 2 diabetes, it does not have a primary role in slowing the progression of diabetic nephropathy. Its mechanism of action is focused on glucose metabolism rather than direct renal protection. Choice B rationale Glipizide is a sulfonylurea medication that stimulates insulin secretion from the pancreatic beta cells, thereby lowering blood glucose levels. Like sitagliptin, its primary function is glucose control in type 2 diabetes. It does not possess specific properties that have been shown to slow the progression of diabetic nephropathy. The long-term management of renal disease requires a different class of medication. Choice C rationale Metoprolol is a beta-blocker that reduces blood pressure and heart rate by blocking the effects of epinephrine and norepinephrine. While controlling hypertension is crucial for managing nephropathy, metoprolol is not the first-line medication for slowing renal disease progression in diabetic patients. The renin-angiotensin system plays a more significant role in diabetic nephropathy, making other drug classes more effective. Choice D rationale Losartan is an angiotensin II receptor blocker (ARB) that works by blocking the binding of angiotensin II to its receptors. This action prevents vasoconstriction and the release of aldosterone, leading to reduced blood pressure and decreased glomerular filtration pressure. ARBs and ACE inhibitors are the preferred medications for slowing the progression of diabetic nephropathy because they specifically target the renin-angiotensin-aldosterone system, which is critically involved in renal injury.