What is the dosage and administration of 1 ampoule of calcium gluconate (calcium) for treating hypocalcemia?

Dosage and Administration of Calcium Gluconate for Hypocalcemia

One ampoule (10 mL) of 10% calcium gluconate contains 90 mg of elemental calcium and should be administered at a rate of 1-2 mg elemental calcium per kilogram body weight per hour for hypocalcemia treatment. 1

Dosing Guidelines

Acute Symptomatic Hypocalcemia

• For mild hypocalcemia (ionized calcium 1.0-1.12 mmol/L):

  • 1-2 g of IV calcium gluconate (effective in 79% of cases) 2
  • Administer at 1 g/hour rate 2

• For moderate to severe hypocalcemia (ionized calcium <1.0 mmol/L):

  • 4 g of IV calcium gluconate (effective in 95% of cases) 3
  • Administer at 1 g/hour rate 3

Post-Parathyroidectomy Hypocalcemia

• Monitor ionized calcium every 4-6 hours for first 48-72 hours after surgery 1
• If ionized calcium falls below normal (<0.9 mmol/L):
  • Initiate calcium gluconate infusion at 1-2 mg elemental calcium per kg body weight per hour 1
  • Adjust to maintain ionized calcium in normal range (1.15-1.36 mmol/L) 1

Administration Method

• Administer through a secure IV line 4, 5
• Central venous access is preferred, especially for continuous infusions 4
• For cardiac arrest situations, administer by slow IV push 4

Monitoring

• For intermittent infusions: Measure serum calcium every 4-6 hours 5
• For continuous infusions: Measure serum calcium every 1-4 hours 5
• Monitor ECG when administering calcium, especially with concomitant cardiac glycosides 5

Important Precautions

Compatibility Issues

• Do not mix calcium gluconate with:
  • Fluids containing phosphate or bicarbonate 4, 5
  • Sodium bicarbonate 4
  • Vasoactive amines 4

Safety Concerns

• Stop infusion if symptomatic bradycardia occurs 4
• Watch for extravasation which can cause severe tissue injury and necrosis 4, 5
• In cardiac arrest due to hyperkalemia or hypermagnesemia, calcium chloride may be preferred due to faster onset of action (calcium chloride [10%] 5-10 mL OR calcium gluconate [10%] 15-30 mL IV over 2-5 minutes) 1

Special Considerations

• For patients with cardiac glycoside therapy, administer calcium slowly in small amounts with close ECG monitoring 5
• Avoid rapid administration which can cause hypotension, bradycardia, and cardiac arrhythmias 5
• For elderly patients, start at the lower end of the dosage range 5

Remember that calcium gluconate is generally safer for peripheral administration, while calcium chloride should be reserved for central line administration due to its higher risk of tissue damage if extravasation occurs 4.