A patient on furosemide reports muscle weakness. Which laboratory result is especially relevant?
- ASerum sodium
- BSerum calcium
- CBlood urea nitrogen
- DSerum potassium
Show answer and explanations
Answer
D
A
Furosemide can lower sodium, but muscle weakness is most characteristic of hypokalemia.
B
Loop diuretics increase calcium loss, but potassium is the key concern with weakness.
C
BUN reflects hydration and renal function; it does not explain muscle weakness the way potassium loss does.
D
Loop diuretics cause potassium loss, and hypokalemia presents with muscle weakness and arrhythmias.