What is the therapy for hypocalcemia (low calcium levels)?

From the Guidelines

The treatment of hypocalcemia should be individualized based on its severity, cause, and symptoms, with a focus on maintaining serum calcium levels in the low-normal range while avoiding hypercalciuria and other complications of treatment. For mild asymptomatic hypocalcemia, oral calcium supplementation with calcium carbonate or calcium citrate at 1-2 grams of elemental calcium daily in divided doses is recommended, along with vitamin D supplementation, typically with calcitriol (0.25-0.5 mcg daily) for active vitamin D or cholecalciferol (1,000-4,000 IU daily) for vitamin D deficiency 1.

Key Considerations

• The underlying cause of hypocalcemia should be addressed simultaneously, whether it's hypoparathyroidism, vitamin D deficiency, chronic kidney disease, or other conditions.
• Regular monitoring of serum calcium, phosphate, magnesium, and vitamin D levels is important to adjust therapy.
• Magnesium deficiency should be corrected if present, as it can impair parathyroid hormone secretion and action.
• For severe symptomatic hypocalcemia with tetany, seizures, or cardiac arrhythmias, immediate intravenous calcium is necessary, usually as calcium gluconate 10% solution (1-2 ampules containing 90-180 mg elemental calcium) given slowly over 10-20 minutes, followed by a continuous infusion of calcium gluconate in severe cases.

Special Populations

• In patients with chronic kidney disease (CKD), the treatment of hypocalcemia should be approached with caution, as higher serum calcium concentrations have been linked to increased mortality and nonfatal cardiovascular events 1.
• In patients with 22q11.2 deletion syndrome, daily calcium and vitamin D supplementation are recommended, along with regular monitoring of calcium concentrations and targeted monitoring at vulnerable times, such as peri-operatively or during severe illness 1.

From the FDA Drug Label

INDICATIONS & USAGE 10% Calcium Chloride Injection, USP is indicated for the treatment of hypocalcemia in those conditions requiring a prompt increase in plasma calcium levels. The therapy for hypocalcemia (low calcium levels) is calcium chloride (IV), specifically 10% Calcium Chloride Injection, USP, for a prompt increase in plasma calcium levels 2.

From the Research

Therapy for Hypocalcemia

The therapy for hypocalcemia (low calcium levels) varies depending on the underlying disorder and the severity of the condition.

• For acute hypocalcemia, intravenous administration of calcium gluconate can rapidly resolve symptoms such as neuromuscular irritability, tetany, and seizures 3, 4, 5.
• For chronic hypocalcemia, oral calcium and/or vitamin D supplementation is commonly used as treatment 3, 6.
• In cases of hypoparathyroidism, providing the missing hormone with the use of recombinant human parathyroid hormone (rhPTH) has been approved by the FDA and EMA, and has been shown to be effective in correcting serum calcium levels and reducing the daily requirements of calcium and active vitamin D supplements 6.
• The treatment of moderate to severe hypocalcemia in critically ill patients is more complex, and may require infusion of calcium gluconate at a rate of 1 g/h in a small-volume admixture 4, 5.
• However, the scientific evidence concerning the correction of hypocalcemia in critically ill patients remains conflicting, and some studies have shown that calcium supplementation did not improve clinical outcomes, such as mortality 7.

Treatment Options

The following treatment options are available for hypocalcemia:

• Intravenous calcium gluconate infusion for acute hypocalcemia 3, 4, 5
• Oral calcium and/or vitamin D supplementation for chronic hypocalcemia 3, 6
• Recombinant human parathyroid hormone (rhPTH) for hypoparathyroidism 6
• Infusion of calcium gluconate at a rate of 1 g/h in a small-volume admixture for moderate to severe hypocalcemia in critically ill patients 4, 5

Considerations

When treating hypocalcemia, it is essential to consider the underlying disorder and the severity of the condition, as well as the potential risks and benefits of treatment 3, 6, 7.

• In patients with hypoparathyroidism, calcium and vitamin D supplementation must be carefully titrated to avoid symptoms of hypocalcemia while keeping serum calcium in the low-normal range to minimize hypercalciuria, which can lead to renal dysfunction 3.
• In critically ill patients, the treatment of hypocalcemia should be individualized, and the potential benefits and risks of treatment should be carefully considered 7.