From the Guidelines
To manage low calcium, it is essential to increase dietary calcium intake and consider supplements, while also addressing underlying conditions and monitoring for potential complications, as recommended by recent guidelines 1.
Key Recommendations
- Increase dietary calcium intake through foods like dairy products, fortified plant milks, leafy greens, and canned fish with bones, aiming for 1,000-1,200 mg of calcium daily.
- Consider calcium supplements, typically calcium carbonate (600 mg elemental calcium per 1,500 mg tablet, taken with food) or calcium citrate (200 mg elemental calcium per 1,000 mg tablet, can be taken without food), if diet alone is insufficient.
- Vitamin D supplementation (800-1,000 IU daily) is crucial for calcium absorption, and prescription-strength vitamin D (50,000 IU weekly) may be necessary for severe deficiency, as suggested by studies 1.
- Ensure adequate magnesium intake and limit substances that deplete calcium, such as excessive sodium, caffeine, and alcohol.
- Regular weight-bearing exercise helps maintain bone density, and monitoring for potential complications, such as hypercalcemia and hypocalcemia, is essential, as highlighted in recent guidelines 1.
Special Considerations
- In patients with chronic kidney disease, treatment should focus on preventing hyperphosphatemia and avoiding hypercalcemia, with a suggested dialysate calcium concentration between 1.25 and 1.50 mmol/L (2.5 and 3.0 mEq/L) 1.
- For adults with 22q11.2 deletion syndrome, daily calcium and vitamin D supplementation are recommended, along with regular monitoring of calcium concentrations and treatment of hypocalcemia, as advised by practical guidelines 1.
Monitoring and Treatment
- Regular monitoring of calcium concentrations, parathyroid hormone, and creatinine levels is necessary to adjust treatment and prevent complications.
- Treatment with hormonally active metabolites of vitamin D may be required for severe hypocalcemia, and consultation with an endocrinologist is recommended.
- Targeted monitoring of calcium concentrations should be considered at vulnerable times, such as peri-operatively, perinatally, or during severe illness, to prevent over-correction and potential complications.
From the FDA Drug Label
The usual adult dosage in hypocalcemic disorders ranges from 200 mg to 1 g (2 -10 mL) at intervals of 1 to 3 days depending on the response of the patient and/or results of serum ionized calcium determinations. The pediatric dosage in hypocalcemic disorders ranges from 2.7 to 5.0 mg/kg hydrated calcium chloride (or 0. 136 to 0.252 mEq elemental calcium per kg, or 0.027 to 0.05 mL of 10% Calcium Chloride Injection per kg). Ionized calcium concentrations should be measured, to assist in dosage adjustment
To manage low calcium (hypocalcemia), administer calcium chloride (IV) as follows:
- Adults: 200 mg to 1 g (2-10 mL) at intervals of 1 to 3 days, depending on patient response and/or serum ionized calcium levels 2.
- Pediatrics: 2.7 to 5.0 mg/kg hydrated calcium chloride (or 0.136 to 0.252 mEq elemental calcium per kg, or 0.027 to 0.05 mL of 10% Calcium Chloride Injection per kg) 2. Key points:
- Monitor ionized calcium concentrations to adjust dosage 2.
- Administer calcium chloride (IV) slowly, preferably in a central or deep vein, at a rate not to exceed 1 mL/min 2.
From the Research
Managing Low Calcium Levels
To manage low calcium levels, also known as hypocalcemia, it is essential to understand the underlying cause of the condition. Hypocalcemia can be acute or chronic and may be caused by various disorders, including hypoparathyroidism and vitamin D deficiency 3, 4.
Treatment Options
Treatment options for hypocalcemia vary depending on the underlying disorder. For acute hypocalcemia, intravenous calcium infusion is often used to rapidly raise calcium levels and resolve symptoms 4, 5. For chronic hypocalcemia, oral calcium and vitamin D supplementation is commonly used 3, 4, 6. In cases of hypoparathyroidism, recombinant human parathyroid hormone (rhPTH) may be used to replace the missing hormone 4.
Calcium Supplementation
When using calcium supplements, it is crucial to choose the correct form and dose. Calcium carbonate and calcium citrate are the most common forms of calcium supplements, with calcium carbonate being the most cost-effective option 6. However, calcium citrate may be preferred in individuals with achlorhydria or those taking certain medications. The maximum dose of elemental calcium that should be taken at a time is 500 mg 6.
Prevention of Hypocalcemia
In some cases, hypocalcemia can be prevented or minimized. For example, routine postoperative administration of vitamin D and calcium can reduce the incidence of symptomatic postoperative hypocalcemia after thyroidectomy 7. The combined administration of both supplements has been shown to be more effective than either supplement alone 7.
Key Considerations
When managing hypocalcemia, it is essential to consider the following: