What is the immediate treatment for hyperkalemia?

Immediate Treatment for Hyperkalemia

For life-threatening hyperkalemia (≥6.5 mEq/L or any ECG changes), immediately administer intravenous calcium to stabilize the cardiac membrane, followed by insulin with glucose and nebulized albuterol to shift potassium intracellularly, then initiate potassium removal strategies including diuretics or hemodialysis. 1

Initial Assessment

Before initiating aggressive treatment, exclude pseudo-hyperkalemia from hemolysis or improper blood sampling by repeating the measurement with appropriate technique 1, 2. Check an ECG immediately, as ECG changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) indicate urgent treatment regardless of the potassium level 1, 2.

Severity Classification

• Mild hyperkalemia: 5.0-5.9 mEq/L 1
• Moderate hyperkalemia: 6.0-6.4 mEq/L 1
• Severe hyperkalemia: ≥6.5 mEq/L (life-threatening) 1

Step 1: Cardiac Membrane Stabilization (Immediate - Within 1-3 Minutes)

Administer intravenous calcium first in any patient with ECG changes or severe hyperkalemia. 1, 3

• Calcium chloride (10%): 5-10 mL (500-1000 mg) IV over 2-5 minutes 1

  • Preferred option as it provides more rapid increase in ionized calcium than calcium gluconate 1
  • Must be given through central venous catheter when possible due to risk of severe tissue injury with extravasation 1

• Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes 1

  • Alternative if peripheral IV access only 1

• Critical caveat: Calcium does NOT lower serum potassium—it only protects against arrhythmias by stabilizing cardiac membranes 1, 3. Effects begin within 1-3 minutes but last only 30-60 minutes, so you must proceed immediately to Steps 2 and 3 1, 2.

• Monitor heart rate during administration and stop if symptomatic bradycardia occurs 1

Step 2: Shift Potassium into Cells (Onset 15-30 Minutes, Duration 4-6 Hours)

Administer all three therapies simultaneously for maximum effect:

Insulin with Glucose (Primary Agent)

• Standard dose: 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1, 2
• Onset within 15-30 minutes, effects last 4-6 hours 1
• Can be repeated every 4-6 hours if hyperkalemia persists, with careful monitoring of glucose and potassium every 2-4 hours 2
• Critical pitfall: Verify potassium is not below 3.3 mEq/L before administering insulin 2
• Patients at highest risk for hypoglycemia: low baseline glucose, no diabetes, female sex, impaired renal function 2

Nebulized Beta-2 Agonist

• Albuterol: 10-20 mg nebulized over 15 minutes 1, 2
• Can reduce serum potassium by approximately 0.5-1.0 mEq/L 1
• Augments the effects of insulin/glucose 4

Sodium Bicarbonate (Only if Metabolic Acidosis Present)

• Dose: 50 mEq IV over 5 minutes 1, 2
• Only use if pH < 7.35 and bicarbonate < 22 mEq/L 2
• Effects take 30-60 minutes to manifest 2
• Promotes potassium excretion through increased distal sodium delivery and counters acidosis-induced potassium release 2

Important warning: All shifting therapies provide only transient effects (1-4 hours), and rebound hyperkalemia can occur after 2 hours 1. You must initiate definitive potassium removal strategies immediately.

Step 3: Eliminate Potassium from Body (Definitive Treatment)

For Patients with Adequate Renal Function

• Loop diuretics: Furosemide 40-80 mg IV 1, 2
• Increases renal potassium excretion 1
• Only effective if patient has adequate kidney function 1

For Patients with Impaired Renal Function or Refractory Cases

• Hemodialysis: Most effective method for severe hyperkalemia, especially with renal failure 1, 3
• Should be used in cases refractory to medical treatment 3

For Subacute Management

• Newer potassium binders (patiromer, sodium zirconium cyclosilicate): Safer alternatives to traditional resins 1, 2
• Sodium polystyrene sulfonate (Kayexalate): 15-50 g orally or rectally with sorbitol 1
  • Reserved for subacute treatment only 5

Ongoing Management

• Monitor potassium levels every 2-4 hours initially to avoid overcorrection and hypokalemia 1, 2
• Review and adjust medications that contribute to hyperkalemia: ACE inhibitors, ARBs, mineralocorticoid antagonists, NSAIDs, beta-blockers 1, 2
• Initiate potassium-lowering agents early to prevent rebound hyperkalemia 1

For Patients on RAAS Inhibitors

• If potassium >5.0 mEq/L: Initiate approved potassium-lowering agent and maintain RAAS inhibitor therapy (these are life-saving medications in cardiovascular disease) 1, 2
• If potassium >6.5 mEq/L: Temporarily discontinue or reduce RAAS inhibitor, initiate potassium-lowering agent, monitor closely 1, 2