How much does 20 mEq of potassium chloride (KCl) raise serum potassium in an adult?

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Expected Serum Potassium Increase With Potassium Chloride

For intravenous potassium chloride, 20 mEq is expected to increase serum potassium by approximately 0.25 mEq/L in an adult. [1]

The expected rise is cited for intravenous administration and may be lower with ongoing potassium losses or impaired repletion conditions. [1]

20 mEq IV potassium chloride → ~0.25 mEq/L serum potassium increase (≈0.1 mEq/L per 10 mEq). [2]

Serum potassium should be reassessed after repletion given variability from baseline potassium, ongoing losses, and renal function. [2]