Live calculator

Electrolyte replacement calculator

Calculate electrolyte deficit and replacement rates for potassium, sodium, and chloride in dogs and cats. Includes safety limits and monitoring guidance. Educational decision-support tool only.

Deficit is calculated using standard distribution factors. Replace electrolytes gradually — rapid correction can be dangerous. Verify all values before administration.

Arithmetic support only. Verify with clinical judgment and current references.
Safety checks
  • This tool supports calculation and education only.
  • It does not diagnose, prescribe, or replace clinical judgment.
  • Rapid electrolyte correction can cause serious complications.
  • Always verify calculations and patient-specific factors.
  • Monitor cardiac rhythm during potassium replacement.
Basis and limits
  • Potassium deficit: mEq = 0.3 × kg × (desired − current). This calculator converts the entered duration into mEq/hr and mEq/kg/hr before deriving an mEq/L additive concentration. It uses 0.5 mEq/kg/hr as the conservative warning threshold; exceptional central-line protocols above this require continuous ECG monitoring and current reference confirmation.
  • Potassium stop point: this replacement calculator blocks potassium supplementation when current K+ is above 5.0 mEq/L.
  • Sodium deficit: mEq = 0.3 × kg × (desired − current). Enter a duration to estimate correction speed; correct chronic or unknown-duration hyponatremia cautiously, commonly at < 0.5 mEq/L/hr.
  • Chloride deficit: mEq = 0.2 × kg × (desired − current). Often corrects with sodium replacement.
  • Scope: this tool provides arithmetic support. It does not replace clinical assessment or monitoring.
Formula audit trail

Calculation steps will appear here for verification.

Last reviewed: May 2026

References: Plumb's Veterinary Drug Handbook, Merck Veterinary Manual, BSAVA Formulary, AAHA Guidelines. Verify against current references before clinical use.