How is oral potassium administered in pediatric patients with hypokalemia?

Oral Potassium Administration in Pediatric Patients with Hypokalemia

For pediatric patients with hypokalemia, oral potassium should be administered at a dose of 1-3 mmol/kg/day divided into multiple doses, with careful monitoring of serum potassium levels to prevent complications. 1

Dosing Guidelines

• For infants and young children, potassium supplementation should be started at 1-3 mmol/kg/day (40-120 mg/kg/day) divided into multiple doses 1
• Potassium chloride (KCl) is the preferred form for most cases of hypokalemia, especially when associated with metabolic alkalosis 2
• Liquid formulations are preferred for pediatric patients who cannot swallow tablets 3
• A simplified extemporaneous preparation can be made using potassium chloride 14.9% diluted with Ora-Sweet SF to create a 1 mmol/mL solution, which remains stable for 28 days when refrigerated 3

Administration Considerations

• Oral administration is preferred over IV when the patient has:
  • A functioning gastrointestinal tract
  • Serum potassium level >2.5 mEq/L
  • No severe symptoms requiring urgent correction 4
• Potassium supplements should be given with adequate fluid intake to ensure proper absorption and prevent gastrointestinal irritation 1
• Potassium supplements should be administered with or after meals to minimize gastrointestinal side effects 1

Monitoring

• Verify potassium levels with a second sample to rule out spurious hyperkalemia from hemolysis during phlebotomy 1
• Monitor serum potassium levels regularly during supplementation, especially in patients with impaired renal function 1
• Monitor for signs of hyperkalemia, including ECG changes, muscle weakness, or paralysis 4
• The expected increase in serum potassium is approximately 0.8 mEq/L per standard dose in pediatric cardiac patients 5

Special Considerations

Medication Interactions

• Responses to potassium supplementation may be:
  • Attenuated by concomitant furosemide, amphotericin B 5
  • Augmented by concomitant ACE inhibitors like enalapril, requiring more cautious dosing 5

Dietary Considerations

• In children with chronic kidney disease who require potassium restriction:
  • Breast milk has lower potassium content (546 mg/L; 14 mmol/L) compared to standard infant formulas (700-740 mg/L; 18-19 mmol/L) 1
  • Volumes of infant formula exceeding 165 mL/kg may aggravate hyperkalemia in susceptible patients 1
  • Foods containing less than 100 mg or less than 3% DV are considered low in potassium 1

Cautions and Contraindications

• Use potassium with extreme caution in patients with cardiac disease, as rapid increases in serum potassium can lead to cardiac arrest even in patients with normal renal function 6
• Avoid potassium-containing salt substitutes in patients at risk for hyperkalemia 1
• For patients with severe hypokalemia (≤2.5 mEq/L), ECG abnormalities, or neuromuscular symptoms, intravenous potassium administration may be necessary 4

Treatment of Hyperkalemia if Overdosed

• For asymptomatic pediatric patients with hyperkalemia, sodium polystyrene sulfonate 1 g/kg with 50% sorbitol can be administered orally 1
• For symptomatic patients, more intensive interventions may be required, including insulin, glucose, sodium bicarbonate, or calcium gluconate 1