What is the dose of Salbutamol (albuterol) for hyperkalemia?

Salbutamol Dose for Hyperkalemia

The recommended dose of nebulized salbutamol (albuterol) for hyperkalemia is 10-20 mg administered over 15 minutes in adults, with onset of action within 15-30 minutes and effects lasting 4-6 hours. 1, 2

Adult Dosing

• Nebulized administration: 10-20 mg of salbutamol nebulized over 15 minutes is the standard dose recommended by the American Heart Association 1, 2
• The medication works by stimulating the Na+/K+-ATPase pump through beta-2 adrenergic receptors, shifting extracellular potassium into cells 2
• Expected potassium reduction: Approximately 0.5-1.0 mEq/L decrease in serum potassium 2
• Onset and duration: Effects begin within 15-30 minutes and last 4-6 hours 2, 3

Pediatric Dosing

For children, the dosing differs significantly from adults:

• Intravenous route: 4 micrograms/kg infused over 20 minutes is effective and safe 4, 5, 6
• This lower IV dose (4 mcg/kg) produces potassium reductions of 1.4-1.6 mEq/L without significant side effects, even in newborns 4
• Older pediatric protocols using 0.5 mg IV (approximately 30 micrograms/min) caused excessive tachycardia, particularly in children 4, 7

Clinical Context and Algorithm

Step 1: Cardiac membrane stabilization (immediate)

• Administer calcium chloride (10%): 5-10 mL IV over 2-5 minutes OR calcium gluconate (10%): 15-30 mL IV over 2-5 minutes 1, 2
• This protects against arrhythmias but does not lower potassium 2

Step 2: Shift potassium into cells (15-30 minute onset)

• Insulin with glucose: 10 units regular insulin IV with 25g glucose (50 mL D50W) over 15-30 minutes 1, 2
• Nebulized salbutamol: 10-20 mg over 15 minutes 1, 2
• Sodium bicarbonate: 50 mEq IV over 5 minutes (only if concurrent metabolic acidosis present) 1, 2

Step 3: Eliminate potassium from body (longer-term)

• Furosemide 40-80 mg IV (if adequate renal function) 1, 2
• Hemodialysis for severe cases or renal failure 2, 3

Important Caveats

Limitations of Salbutamol Therapy

• Temporary effect only: Salbutamol provides transient potassium lowering, and rebound hyperkalemia can occur after 2 hours 2, 3
• Does not increase excretion: The drug only shifts potassium intracellularly; it does not eliminate potassium from the body 2
• Requires repeat dosing: May need to be repeated as effects wear off after 4-6 hours 2

Side Effects to Monitor

• Tachycardia: Most common side effect, occurring in up to 90% of patients 8, 7
• Hypotension: Significant decreases in blood pressure can occur (systolic drop from 134 to 119 mmHg, diastolic from 74 to 65 mmHg) 8
• Other effects: Fine tremor, anxiety, increased respiratory rate 8
• These side effects are generally moderate and well-tolerated 8

Efficacy Considerations

• Less effective in metabolic acidosis: In patients with persistent metabolic acidosis without renal failure, salbutamol may be ineffective and potassium levels may continue to rise 5
• Most effective in renal failure: Achieves temporary reduction in hyperkalemia in patients with acute renal failure 5
• No correlation with severity: The magnitude of potassium decrease does not correlate with the initial degree of hyperkalemia 8

Practical Implementation

• Monitoring required: Check potassium levels every 2-4 hours after administration 3
• Combination therapy: Salbutamol should be used as part of a multi-step approach, not as monotherapy 1, 2
• Definitive treatment needed: Address underlying cause and consider potassium binders for chronic management 2, 3