What is the treatment for hypocalcemia?

Treatment of Hypocalcemia

The treatment of hypocalcemia should include calcium supplementation with doses adjusted based on severity, along with vitamin D therapy targeting 25-hydroxyvitamin D levels >30 ng/mL, and addressing the underlying cause. 1

Initial Assessment and Acute Management

Severe Symptomatic Hypocalcemia

• Intravenous calcium administration is essential for acute, severe hypocalcemia 1, 2
  • Calcium gluconate: 1-2g IV for mild hypocalcemia, 2-4g for moderate-severe hypocalcemia
  • Calcium chloride: Administer by slow push for cardiac arrest, infused over 30-60 minutes for other indications
  • Central venous catheter preferred for calcium chloride to avoid tissue injury from extravasation 1

Monitoring During Acute Treatment

• Monitor ionized calcium levels frequently during treatment
• Watch for cardiac arrhythmias and adjust infusion rate if symptomatic bradycardia occurs
• Monitor for complications of IV calcium including extravasation and tissue necrosis 1

Chronic Management

Calcium Supplementation

• Oral calcium: 1000-2000 mg elemental calcium daily 1
  • Calcium carbonate: 1-2g three times daily for post-parathyroidectomy hypocalcemia
  • Adjust doses upward until normal serum calcium levels are achieved
  • Total daily calcium intake should not exceed 2.0g/day in CKD patients 1

Vitamin D Therapy

• Target 25-hydroxyvitamin D levels >20-30 ng/mL 3, 1
  • Native vitamin D (cholecalciferol or ergocalciferol) supplementation: 800-1000 IU daily 1
  • Active vitamin D (calcitriol): Up to 2 μg/day when oral intake is possible, especially for post-parathyroidectomy hypocalcemia 1

Special Considerations for Specific Causes

Hypoparathyroidism

• Calcium and vitamin D supplementation must be carefully titrated
• Keep serum calcium in low-normal range to minimize hypercalciuria 4
• Recombinant human PTH(1-84) may be considered for patients with difficult-to-control hypoparathyroidism 2

Chronic Kidney Disease

• Use dialysate calcium concentration between 1.25-1.50 mmol/L (2.5-3.0 mEq/L) for dialysis patients 1
• Individualize treatment for hypocalcemia in CKD patients on calcimimetics 1
• For elevated PTH levels while on therapy with oral phosphate and active vitamin D:
  • Increase dose of active vitamin D and/or decrease dose of oral phosphate supplements 3
  • In case of persistent hypercalciuria/hypercalcemia, reduce or stop active vitamin D and phosphate supplements 3

Monitoring and Follow-up

• Check ionized calcium levels every 3-6 months until stable, then annually
• More frequent monitoring for patients with chronic kidney disease
• Monitor 25-hydroxyvitamin D levels and adjust supplementation accordingly 1
• Calculate corrected calcium when albumin is abnormal: Corrected calcium (mg/dL) = Total calcium (mg/dL) + 0.8 × [4 - Serum albumin (g/dL)] 1

Common Pitfalls and Caveats

• Avoid aggressive correction in all cases - individualize treatment based on severity and underlying cause 1
• Total calcium may not accurately reflect ionized calcium status, especially in patients with hypoalbuminemia or acid-base disturbances 1
• Potential complications of treatment include overcorrection leading to hypercalcemia, renal calculi formation, and renal failure 1
• Avoid concurrent use of calcium with ceftriaxone due to risk of precipitates 1
• Consider discontinuing or modifying medications that can cause hypocalcemia (bisphosphonates, PPIs, loop diuretics, anticonvulsants, etc.) 1
• Calcium supplements can cause constipation, bloating, kidney stones, and possibly increased risk of myocardial infarction 5
• High-dose vitamin D can result in more falls and fractures, so appropriate dosing is critical 5