Calcium gluconate

General

  • Type: Electrolyte
  • Dosage Forms: injectable solution, tablet, capsule
  • Dosage Strenths: injectable solution: 100mg/mL; tablet: 50, 500, 650mg; capsule: 500mg
  • Routes of Administration: PO, IV
  • Common Trade Names:

Adult Dosing

  • Calcium Supplementation
    • 19-50 years old: 1000mg/day PO (divided q8-12hr)
    • >50 years old: 1200mg/day PO (divided q8-12hr)
    • Pregnant or breastfeeding patient: 1000mg/day PO (divided q8-12hr)
  • Hypocalcemia
    • Mild (Calcium 1-1.2 mmol/L)
      • 1-3 g/day PO in divided doses
      • 1-2 g IV over 2 hours
    • Severe (Calcium < 1 mmol/L)
      • without seizure or tetany: 0.5mg/kg/hr IV, may be increased to 2mg/kg/hr
      • Hypocalcemic tetany:
        • 100-300mg elemental calcium (~3g calcium gluconate) IV over 5-10 min
        • Followed by continuous IV infusion at 0.5mg/kg/hr
  • Calcium channel blocker toxicity: 3g IV (30-60mL of 10% soln)
  • Beta blocker toxicity: 3g IV (30-60mL of 10% soln)
  • Hyperkalemia: Give 10ml of a 10% solution over 10 mins
  • Hydrofluoric acid toxicity:[1]
    • 25ml 10% calcium gluconate mixed with 75ml water soluble lubricant applied topically
    • In severe cases, can infuse 10ml 10% calcium gluconate mixed in 40mL of D5W through arterial catheter over 4 hours

Pediatric Dosing

  • Hypocalcemia
    • Children: 200 to 500 mg IV (slow injection)
    • Infants: up to 200 mg IV (slow injection
  • Seizure due to hypocalcemia: 10% calcium gluconate IV 0.3 mL/kg over 5-10min

Special Populations

  • Pregnancy Rating: C
  • Lactation risk: Use with caution
  • Renal Dosing:
    • CrCl less than 25 mL/min, base dosing on serum calcium levels
    • ESRD: if on HD, may need dose reduction
  • Hepatic Dosing: No adjustment

Contraindications

  • Hypersensitivity
  • Hypercalcemia
  • Ventricular fibrillation
  • Digoxin toxicity (known or suspected)
  • Neonates receiving ceftriaxone sodium injection

Adverse Reactions

Serious

  • Bradycardia, vasodilation, hypotension, MI, cardiac arrest
  • Tissue necrosis (due to extravasation)
  • Urolithiasis
  • Prostate cancer

Common

  • Constipation, abdominal bloating, flatulence
  • Headache

Pharmacology

  • Half-life:
  • Metabolism:
    • Absorption requires Vitamin D
    • Absorption is increased with acidic condition; thus, administer 1-2 hr after meals
    • ~45% protein bound (primarily to albumin)
  • Excretion: feces as unabsorbed calcium salt (80%), urine (20%)

Mechanism of Action

  • Bone mineral component; cofactor in enzymatic reactions, essential for neurotransmission, muscle contraction, and many signal transduction pathways.

Comments

See Also

References

  1. Su M. Hydrofluoric Acid. In: Goldfrank’s Toxicologic Emergencies, 10e. 2016.