Please note: this guideline has exceeded its review date and is currently under review by specialists. Exercise caution in the use of the clinical guideline. A partial update to the guideline was made in July 2023 to align with the NPSA alert regarding the dosing and administration of calcium gluconate. 

Management of Hyperkalaemia (plasma K+ >5.5mmol/L)

Assessment / monitoring

  • Plasma potassium
  • ECG monitoring

General management

  • Exclude spurious hyperkalaemia (venous blood gas sample in emergency or seek advice from Biochemistry) and check for ECG changes.
  • Identify and treat underlying cause where possible:
    • Potassium supplements, ACE inhibitors, potassium-sparing diuretics and spironolactone should be discontinued.
    • Renal failure – consider referral to renal unit.
    • Hypovolaemia – consider volume expansion with IV sodium chloride 0.9%.
    • Severe acidosis (often associated with renal failure).
    • Hypoaldosteronism, e.g. Addison's disease.
  • If hyperkalaemia remains unexplained, more specialised investigation may be appropriate. Advice may be obtained from your local Biochemistry Department.

Drug therapy / treatment options

    1. Confirmed plasma K+ 5.5–6.5mmol/L

      Calcium Resonium® oral 15g three times daily (in water not fruit juice).

      • Calcium Resonium will not lower potassium acutely. It is only licensed for hyperkalaemia due to anuria or oliguria.
      • Resonium A® can be used if there is a risk of hypercalcaemia.
      • Monitor plasma K+ daily until K+ <5.5mmol/L.
    2. Confirmed plasma K+ >6.5mmol/L and/or ECG changes (although treatment should not be delayed, result should be confirmed):

      30ml calcium gluconate 10% – IV bolus injection over 10 minutes given by a doctor (to antagonise the effect of potassium on the heart).

      8units soluble insulin (Actrapid®) in 100ml IV glucose 20% vial over 30 minutes (to move potassium into the cells). This may be repeated once and/or followed by an infusion of the same mixture at 5–10ml/hour.


      5–10mg nebulised salbutamol.


  • Calcium gluconate may be repeated after 5 to 10 minutes if ECG changes persist.
  • Check plasma K+ and glucose one hour after glucose / insulin infusion.
  • Glucose / insulin infusions should be repeated until plasma K+ <6.5mmol/L.
  • Hyperosmolar glucose infusions should not be used in diabetic ketoacidosis.


Content last reviewed October 2018