What is the treatment for hyperkalemia (elevated potassium levels)?

Treatment of Hyperkalemia

Immediate Assessment and Risk Stratification

The urgency and intensity of treatment depends on the potassium level, ECG changes, and clinical symptoms—with severe hyperkalemia (>6.5 mmol/L) or any ECG changes requiring immediate emergency treatment. 1

• Verify the result immediately with a second sample to rule out pseudohyperkalemia from hemolysis during phlebotomy 1
• Obtain an ECG immediately to assess for cardiac toxicity 1
• ECG changes progress with severity: peaked T waves → flattened P waves → prolonged PR interval → widened QRS → sine-wave pattern → cardiac arrest 1
• Immediate intervention is indicated if potassium >7.0-7.5 mEq/L or ECG shows QRS widening 1

Emergency Treatment (Severe Hyperkalemia: >6.5 mmol/L or ECG Changes)

Step 1: Stabilize the Myocardial Membrane (Acts in Minutes)

• Calcium chloride 10%: 5-10 mL (500-1000 mg) IV over 2-5 minutes OR calcium gluconate 10%: 15-30 mL IV over 2-5 minutes 1
• Alternatively, calcium gluconate 50-100 mg/kg IV administered slowly with continuous ECG monitoring for bradycardia 1
• This does not lower potassium but protects against arrhythmias 1

Step 2: Shift Potassium into Cells (Acts in 15-60 Minutes, Temporary Effect)

Administer multiple agents simultaneously for additive effect:

• Insulin + Glucose: Mix 10 U regular insulin with 25 g glucose (50 mL D50) IV over 15-30 minutes 1
  • For pediatrics: 0.1 U/kg insulin IV with 25% dextrose 2 mL/kg 1
• Nebulized albuterol: 10-20 mg over 15 minutes 1
• Sodium bicarbonate: 50 mEq IV over 5 minutes (particularly if metabolic acidosis present) 1
  • For pediatrics: 1-2 mEq/kg IV push 1
• Important caveat: These agents only provide temporary benefit (1-4 hours) and rebound hyperkalemia can occur after 2 hours, so potassium removal must be initiated simultaneously 1

Do not administer sodium bicarbonate and calcium through the same IV line 1

Step 3: Remove Potassium from the Body (Acts in Hours)

• Loop diuretics: Furosemide 40-80 mg IV to increase renal excretion 1
• Sodium polystyrene sulfonate (Kayexalate): 15-50 g plus sorbitol orally or rectally 1
  • For pediatrics: 1 g/kg with 50% sorbitol orally or rectally (avoid rectal route in neutropenic patients) 1
  • FDA limitation: Not for emergency treatment due to delayed onset of action 2
  • Avoid chronic use with sorbitol due to severe gastrointestinal side effects including colonic necrosis 3
• Hemodialysis for refractory cases or when other measures are ineffective 1

Subacute Treatment (Moderate Hyperkalemia: 5.5-6.5 mmol/L)

For Asymptomatic Patients Without ECG Changes:

• Eliminate all oral and IV sources of potassium 1
• Sodium polystyrene sulfonate 1 g/kg with sorbitol orally or rectally 1
• If on mineralocorticoid receptor antagonists (MRAs), halve the dose when potassium >5.5 mmol/L 1, 3, 4
• Consider discontinuing MRAs if potassium exceeds 6.0 mmol/L 3
• Increase monitoring frequency beyond standard 4-month intervals 3, 4

Mild Hyperkalemia (5.1-5.5 mmol/L)

Initial Management:

• Implement dietary potassium restriction as first-line intervention 3, 4
  • Limit high-potassium foods: bananas, oranges, potatoes, tomato products, legumes, yogurt, chocolate 1
  • Presoaking root vegetables lowers potassium by 50-75% 1
  • Avoid salt substitutes containing potassium 1
• Eliminate potassium supplements and review medications 3
• Discontinue NSAIDs and other medications that impair renal function 3
• No need to reduce ACE inhibitors/ARBs at this level—dose adjustment only recommended when potassium exceeds 5.5 mmol/L 3

Medication Adjustments:

• For patients on RAASi at maximal tolerated dose, maintain current dose and monitor closely 3
• Consider increasing non-potassium-sparing diuretics if appropriate 3

Chronic Management and Prevention

• Target potassium ≤5.0 mmol/L, as recent evidence suggests this is the upper limit of safety, particularly in patients with heart failure, CKD, or diabetes 3, 4
• Optimal range may be 3.5-4.5 mmol/L or 4.1-4.7 mmol/L based on mortality data 3, 4
• Monitor more frequently than every 4 months in high-risk patients 3, 4
• Consider newer potassium binders (patiromer, sodium zirconium cyclosilicate) for chronic hyperkalemia if available 3

Critical Pitfalls to Avoid

• Do not prematurely discontinue beneficial RAASi medications for mild hyperkalemia (5.1-5.5 mmol/L), as this offsets survival benefits 1, 3
• Do not rely on sodium polystyrene sulfonate alone for chronic management due to gastrointestinal toxicity risk 3
• Do not use sodium polystyrene sulfonate as emergency treatment—it has delayed onset of action 2
• Do not give bolus potassium for cardiac arrest suspected to be from hypokalemia—this is ill-advised 1
• Remember that insulin/albuterol/bicarbonate effects are temporary (1-4 hours) and rebound hyperkalemia can occur, requiring simultaneous initiation of potassium removal strategies 1

Special Populations

Tumor Lysis Syndrome:

• Eliminate all potassium sources as long as TLS risk exists 1
• Monitor potassium every 4-6 hours after chemotherapy initiation 1

Chronic Kidney Disease:

• Patients on frequent hemodialysis (5 sessions/week) or peritoneal dialysis rarely need restriction and may develop hypokalemia 1
• Investigate non-dietary causes: hemolysis, acidosis, constipation, inadequate dialysis, tissue destruction 1