Potassium homeostasis: cellular shifts: practice question

A Physiology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Physiology · Potassium homeostasis: cellular shifts

Sample item

A patient with potassium 6.8 mmol/L and peaked T waves needs a rapid reduction in serum potassium. Which treatment acts mainly by moving potassium into cells?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

C. Intravenous insulin with glucose

Insulin stimulates Na+-K+ ATPase and Na+-H+ exchange in muscle and liver, driving potassium into cells within minutes; beta-2 agonists act similarly. Acidosis does the opposite, shifting potassium out of cells. Calcium protects the myocardium but does not change serum potassium, while diuretics and resins remove potassium from the body more slowly.

Option by option

  • A. Intravenous furosemide

    Furosemide increases renal potassium excretion, a slower route that does not shift potassium into cells.

  • B. Oral cation-exchange resin

    Resins bind potassium in the gut, a slow route that does not shift potassium into cells.

  • C. Intravenous insulin with glucose (correct)

    Correct. Insulin promotes cellular uptake of potassium and acts within minutes.

  • D. Intravenous calcium gluconate

    Calcium stabilises the cardiac membrane threshold but leaves serum potassium unchanged.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

More Physiology questions

Questions about this Physiology question

What is the answer to this Physiology question?

The best answer is C, Intravenous insulin with glucose. Insulin stimulates Na+-K+ ATPase and Na+-H+ exchange in muscle and liver, driving potassium into cells within minutes; beta-2 agonists act similarly.

Why is "Intravenous furosemide" not the answer?

Furosemide increases renal potassium excretion, a slower route that does not shift potassium into cells.

Why is "Oral cation-exchange resin" not the answer?

Resins bind potassium in the gut, a slow route that does not shift potassium into cells.

Why is "Intravenous calcium gluconate" not the answer?

Calcium stabilises the cardiac membrane threshold but leaves serum potassium unchanged.

What concept does this question test?

It tests Potassium homeostasis: cellular shifts in Physiology. Acidosis does the opposite, shifting potassium out of cells. Calcium protects the myocardium but does not change serum potassium, while diuretics and resins remove potassium from the body more slowly.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Potassium homeostasis: cellular shifts?

For each system, sketch the key graph (pressure–volume loop, oxygen dissociation curve, nephron handling) and explain it aloud. Then use the flashcards and the other Physiology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.