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

This guideline has been updated to reflect the UK Kidney Association Treatment of Acute Hyperkalaemia in Adults (October 2023) - search here. It is an interim update whilst review is undertaken on the choice of calcium IV preparation in GGC, prompted by the Drug Safety Alert issued by the MHRA (June 2023) - search here

This guideline is supported by the Medicines Update (MU) Blog article on the management of acute hyperkalaemia, which highlights the key messages and changes - search here.  

Assessment / monitoring

  • Assess clinical status of the patient
  • Perform immediate 12-lead ECG on the patient if K+ ≥6mmol/L
    • If ECG changes - seek senior help and follow the flowchart for immediate management.
    • If no ECG change, exclude spurious hyperkalaemia and repeat blood sample.

General management

  • Check for ECG changes and initiate emergency management as appropriate.
  • If patient is on long-term dialysis - contact the On-call Renal Registrar immediately.
  • Identify and treat underlying cause where possible:
    • Potassium supplements, ACE inhibitors, angiotensin receptor blockers, potassium-sparing diuretics and spironolactone or eplerenone should be withheld until the hyperkalaemia resolves, then consider re-initiating.
    • Renal failure – consider referral to the Renal Unit.
    • Hypovolaemia – consider volume expansion with sodium chloride 0.9% IV.
    • Severe acidosis (often associated with renal failure).
    • Hypoaldosteronism, e.g. insufficient steroid dosing or Addison's disease.
    • Poorly controlled glycaemia in insulin dependent diabetes.
  • If hyperkalaemia remains unexplained, more specialised investigation may be appropriate. Advice may be obtained from your local Biochemistry Department.

Drug therapy / treatment options

See the flowchart for the management of mild, moderate and severe hyperkalaemia. Below are additional notes to accompany the guidance in the flowchart.

Additional notes to accompany the flowchart:

Mild hyperkalaemia

Confirmed plasma K+ 5.5 – 5.9mmol/L:

  • Consider causes and need for treatment - often medication or dietary changes are all that are required.
  • Arrange appropriate monitoring.

Severe hyperkalaemia

Confirmed plasma K+ ≥6.5mmol/L and/or ECG changes (although treatment should not be delayed, result should be confirmed):

  • Seek senior support
  • Ensure continuous cardiac monitoring
  • Sodium bicarbonate IV (under senior / expert advice):
    • should only be considered if patient has metabolic acidosis (H+ >60nmol/L or HCO3 <17mmol/L) or cardiac arrest.
    • monitor calcium level and fluid status.
  • If K+ >6.5mmol/L despite the medication options outlined in the flowchart, refer to the On-call Renal Registrar as dialysis may be considered.
  • Recheck serum K+ at 1 hour, 4 hours, 6 hours and 24 hours following treatment.
  • Reduce the risk of hypoglycaemia. Check capillary blood glucose (CBG) before commencing insulin-glucose infusion, following the infusion and then at 30mins, 60mins, 90mins, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 8 hours and 12 hours post-infusion.
  • Discuss with the On-call Renal Registrar if inadequate response is predicted from medical management.

Further notes

  • Calcium IV may be repeated after 5 minutes if ECG changes persist. Ensure continuous ECG monitoring.
  • Glucose infusion may not be required in diabetic ketoacidosis.
  • Salbutamol should not be used as monotherapy as some patients will not respond to it.
  • Patiromir sorbitex calcium may be used if the patient is intolerant to sodium zirconium cyclosilicate (Lokelma®).


Guideline reviewed: May 2024

Page updated: May 2024