Which mineral supplement can cause hyperkalemia if taken in excess, especially in people with kidney disease?

• A. Calcium
• B. Sodium
• C. Iron
• D. Potassium

Answer: (D)

Potassium is the mineral whose excess directly raises serum potassium levels. In people with kidney disease, the kidneys’ ability to excrete potassium is reduced, so taking potassium supplements can easily push potassium into a dangerous range. Hyperkalemia can affect heart rhythm and muscle function, making it a critical risk with potassium intake in CKD.

The other minerals don’t carry this same risk in the same way. Excess calcium can lead to high calcium levels, iron overload causes iron toxicity, and too much sodium leads to high sodium levels, but none are as directly linked to hyperkalemia as potassium is. So potassium is the mineral supplement most likely to cause hyperkalemia, especially when kidney function is impaired.