How does insulin affect potassium levels?

• A. Insulin has no effect on potassium levels.
• B. Insulin can lower potassium levels by driving potassium into cells.
• C. Insulin increases potassium levels in the bloodstream.
• D. Insulin decreases potassium absorption in the intestines.

Answer: (B)

Insulin plays a crucial role in regulating potassium levels in the body, primarily by facilitating the movement of potassium from the extracellular space into the cells. When insulin is released, it stimulates the uptake of glucose by cells; simultaneously, it promotes the activity of the sodium-potassium ATPase pump. This pump actively transports potassium into the cells while promoting the movement of sodium out.

As a result, when insulin is administered, particularly in situations such as treatment for diabetic ketoacidosis or hyperglycemic emergencies, it can effectively lower potassium concentrations in the bloodstream. This is significant in clinical settings, as high potassium levels (hyperkalemia) can lead to serious cardiac complications. Thus, the correct choice highlights insulin's role in driving potassium into cells, thereby reducing its overall concentration in the blood.