What is the treatment for hyperkalemia?

Treatment of High Potassium (Hyperkalemia)

For severe hyperkalemia (≥6.5 mEq/L) or any level with ECG changes, immediately administer IV calcium for cardiac protection, followed by insulin with glucose and nebulized albuterol to shift potassium intracellularly, then use loop diuretics or hemodialysis to remove potassium from the body. 1, 2

Initial Assessment

Before initiating treatment, verify this is true hyperkalemia and not pseudohyperkalemia from hemolysis, repeated fist clenching, or poor phlebotomy technique 1, 2. Obtain an ECG immediately—look for peaked T waves, flattened P waves, prolonged PR interval, and widened QRS complexes, though these findings are highly variable and less sensitive than laboratory values 1, 2. Do not rely solely on ECG findings to exclude severe hyperkalemia, as ECG changes can be absent even with dangerously elevated potassium 1.

Classify severity: mild (5.0-5.9 mEq/L), moderate (6.0-6.4 mEq/L), or severe (≥6.5 mEq/L) 1, 2.

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

Administer IV calcium immediately if potassium ≥6.5 mEq/L or any ECG changes are present 1, 2:

• Calcium chloride 10%: 5-10 mL (500-1000 mg) IV over 2-5 minutes (preferred, provides more rapid increase in ionized calcium) 2, 3
• Alternative: Calcium gluconate 10%: 15-30 mL IV over 2-5 minutes 1, 2

Effects begin within 1-3 minutes but last only 30-60 minutes 1, 2, 3. Calcium does not lower serum potassium—it only protects against arrhythmias 1, 2. Administer through central line when possible, as extravasation can cause severe tissue injury 2. Monitor heart rate and stop if symptomatic bradycardia occurs 2. Avoid calcium in patients taking digoxin due to risk of potentiation of digoxin toxicity 3.

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

Initiate these therapies simultaneously for additive effect:

Insulin with glucose (most effective agent for acute potassium lowering) 3:

• 10 units regular insulin IV with 50 mL of D50W (25g glucose) over 15-30 minutes 1, 2, 3
• Pediatric dose: 0.1 units/kg insulin with 400 mg/kg glucose 3
• Can be repeated every 4-6 hours if hyperkalemia persists, monitoring potassium every 2-4 hours and glucose frequently to prevent hypoglycemia 1, 3
• Patients at higher risk for hypoglycemia include those with low baseline glucose, no diabetes, female sex, and altered renal function 1

Nebulized beta-2 agonist 1, 2:

• Albuterol 10-20 mg nebulized over 15 minutes 1, 2
• Effects last 2-4 hours 1
• Can reduce potassium by 0.5-1.0 mEq/L 2

Sodium bicarbonate (ONLY if concurrent metabolic acidosis present) 1, 2:

• 50 mEq IV over 5 minutes if pH <7.35 and bicarbonate <22 mEq/L 1, 2
• Effects take 30-60 minutes to manifest 1
• Do not use in patients without metabolic acidosis—it is only indicated when acidosis is present 1
• Works by increasing distal sodium delivery and countering acidosis-induced potassium release 1

Step 3: Remove Potassium from Body (Definitive Treatment)

Loop diuretics (for patients with adequate renal function) 1, 2:

• Furosemide 40-80 mg IV 1, 2
• Promotes urinary potassium excretion by increasing flow to renal collecting ducts 1

Hemodialysis (most effective method for severe hyperkalemia) 1, 2, 3:

• Indicated for severe hyperkalemia unresponsive to medical management, oliguria, end-stage renal disease, or hemodynamic instability 1, 4
• Most reliable method to remove potassium from the body 1, 5

Newer potassium binders (for chronic management or subacute treatment) 6, 1:

• Sodium zirconium cyclosilicate (SZC): 10g dose reduces potassium within 1 hour 6, 1
• Patiromer: also FDA-approved for chronic hyperkalemia 1
• These agents are now preferred over older agents for long-term management 1

Sodium polystyrene sulfonate (Kayexalate) 7:

• Should NOT be used as emergency treatment due to delayed onset of action 7
• Has significant limitations including risk of bowel necrosis 1
• Reserved for subacute treatment only 8

IV Fluid Management

Use normal saline (0.9% NaCl) for volume expansion and improved renal perfusion 3. Avoid potassium-containing fluids such as Lactated Ringer's 3. Normal saline alone is insufficient and must be combined with insulin/glucose or other potassium-lowering strategies 3.

Chronic Hyperkalemia Management in Patients on RAAS Inhibitors

For patients on ACE inhibitors, ARBs, or mineralocorticoid antagonists with potassium 5.0-6.5 mEq/L: Initiate an approved potassium-lowering agent (patiromer or SZC) and maintain RAAS inhibitor therapy rather than discontinuing these life-saving medications 1, 2.

For potassium >6.5 mEq/L: Temporarily discontinue or reduce RAAS inhibitor, initiate potassium-lowering agent when levels >5.0 mEq/L, and monitor closely 1, 2.

Check potassium within 1 week of starting or escalating RAAS inhibitors, with reassessment 7-10 days after dose changes 1.

Critical Pitfalls to Avoid

• Temporary measures (calcium, insulin/glucose, albuterol) provide only transient effects lasting 1-6 hours—rebound hyperkalemia can occur after 2 hours 1, 2. Initiate definitive potassium removal strategies early 2.
• Do not rely solely on ECG findings—they are highly variable and less sensitive than laboratory tests 1.
• Always administer glucose with insulin to prevent hypoglycemia 3.
• Remember that calcium, insulin, and beta-agonists do not remove potassium from the body—they only temporize 1.
• Exclude pseudohyperkalemia before initiating aggressive treatment 2.

Monitoring Protocol

• Check potassium at 1-2 hour intervals during acute treatment 3
• Monitor blood glucose frequently to prevent hypoglycemia 3
• Observe ECG changes for worsening or improvement 3
• Watch for rebound hyperkalemia 2-4 hours after treatment 3
• More frequent monitoring required in high-risk patients with chronic kidney disease, heart failure, or diabetes 1

Medications Contributing to Hyperkalemia

Review and adjust: ACE inhibitors, ARBs, mineralocorticoid antagonists, NSAIDs, beta-blockers, and heparin 1, 2.