Empagliflozin blocks which transporter?

• A. Sodium glucose cotransporter 2 (SGLT2)
• B. Sodium glucose cotransporter 1 (SGLT1)
• C. GLUT4
• D. Na+/K+ ATPase

Answer: (D)

Empagliflozin works by blocking the transporter responsible for reclaiming glucose in the kidney. It inhibits SGLT2 in the proximal tubule, which normally reabsorbs most of the filtered glucose along with sodium. When SGLT2 is blocked, less glucose is reabsorbed, so more is excreted in the urine (glucosuria) and blood glucose falls.

SGLT1 is a related transporter that handles glucose uptake mainly in the gut and also a smaller role in the kidney, but empagliflozin targets SGLT2 specifically. GLUT4 is the insulin-responsive glucose transporter in muscle and adipose tissue, not involved in renal glucose reabsorption. Na+/K+ ATPase is the basolateral sodium pump that maintains ion gradients; it does not transport glucose and is not the target of this drug.