Safe Sodium Correction Rate
Enter current sodium, target sodium, and timeframe to review the hourly and daily correction rates relative to guideline thresholds.
Total sodium change
8.0 mEq/L
Hourly rate
0.33 mEq/L/hr
Daily equivalent
8.0 mEq/L/day
How to Use This Calculator
Determine starting sodium and goal
Set a realistic target sodium based on chronicity of dysnatremia (often 4–8 mEq/L change in 24 hours for chronic cases).
Enter planned timeframe
Use the intended duration for achieving the target sodium (commonly 24 hours). The calculator converts to hourly and daily rates.
Check against safety thresholds
Ensure rate ≤8 mEq/L/day for chronic hyponatraemia and ≤10–12 mEq/L/day for hypernatremia. Adjust fluids or therapy accordingly.
Formula
ΔNa⁺ = Target Na⁺ − Initial Na⁺
Hourly rate = ΔNa⁺ ÷ Time (hours)
Daily equivalent = Hourly rate × 24
Full Description
Rapid correction of sodium disorders risks catastrophic neurologic injury. In chronic hyponatraemia, overcorrection can cause osmotic demyelination; in hypernatremia, too-rapid decline can precipitate cerebral oedema. This calculator translates planned targets into hourly and daily rates so clinicians can compare with guideline limits and adjust fluid or electrolyte therapy before initiating treatment.
Frequently Asked Questions
What rate is safe for chronic hyponatraemia?
Most guidelines recommend ≤8 mEq/L increase in 24 hours (maximum 10 mEq/L). Slower targets (4–6 mEq/L) are safer for high-risk patients (alcoholism, malnutrition).
How about acute hyponatraemia?
Acute (<48 h) symptomatic hyponatraemia may require faster correction initially (up to 4–6 mEq/L in several hours) under close monitoring. Adjust targets accordingly.
What is the safe decline for hypernatremia?
Lower sodium no faster than 10–12 mEq/L per day (0.5 mEq/L/hr) to minimise risk of cerebral oedema, especially in chronic hypernatremia.
How often should sodium be checked?
Typically every 2–4 hours during active correction. Adjust therapy based on trends to stay within safety thresholds.