What is the equivalent amount of calcium chloride for 1 gram of calcium gluconate?

Calcium Equivalence: Calcium Gluconate vs. Calcium Chloride

1 gram of calcium gluconate is equivalent to approximately 0.33 grams of calcium chloride based on elemental calcium content.

Elemental Calcium Content Comparison

The equivalence between calcium gluconate and calcium chloride is determined by their elemental calcium content:

• Calcium Gluconate: Contains 9.3 mg (0.465 mEq) of elemental calcium per 100 mg 1

  • Therefore, 1 gram (1000 mg) of calcium gluconate contains 93 mg of elemental calcium

• Calcium Chloride: Contains approximately 27 mg of elemental calcium per 100 mg 2

  • Therefore, 100 mg of calcium chloride contains about 27 mg of elemental calcium

Conversion Calculation

To determine how much calcium chloride provides the same amount of elemental calcium as 1 gram of calcium gluconate:

1. Elemental calcium in 1 gram of calcium gluconate = 93 mg
2. Amount of calcium chloride needed = 93 mg ÷ 27 mg/100 mg = 344 mg (approximately 0.33 grams)

Clinical Applications

Intravenous Administration

• When substituting calcium chloride for calcium gluconate in emergency situations:
  • 4.4 mL of 7.35% calcium chloride or 2.2 mL of 14.7% calcium chloride is equivalent to 10 mL of 10% calcium gluconate 3
  • Each 10 mL vial of 10% calcium gluconate contains 2.2 mmol of calcium 3

Peripheral vs. Central Administration

• Calcium gluconate is preferred for peripheral IV administration due to less irritation to veins 3
• Calcium chloride should only be administered via a central line due to its higher irritant potential 3
• In shortage situations, compounded calcium chloride admixtures in 5% dextrose (diluted solutions) can be considered for peripheral administration with careful monitoring 4

Efficacy Considerations

• Both calcium chloride and calcium gluconate are equally effective in treating ionic hypocalcemia, even in patients without hepatic function 5
• Calcium chloride does not require hepatic metabolism for the release of ionized calcium 5
• Both forms produce similar increases in ionized calcium concentrations when administered in equivalent elemental calcium doses 2

Important Clinical Considerations

• When selecting between calcium preparations, consider:

  1. Route of administration (peripheral vs. central)
  2. Patient's vascular access
  3. Clinical urgency (calcium chloride may provide more rapid correction in critical situations)
  4. Availability of preparations (especially during shortages)

• For oral supplementation, calcium carbonate is the most cost-effective form, providing 40% elemental calcium 6

• In emergency management of hypocalcemia, the maximum dose of elemental calcium that should be administered at one time is 500 mg 6

Remember that calcium chloride is approximately three times more potent in terms of elemental calcium content than calcium gluconate, so dosing must be adjusted accordingly when substituting one for the other.