From the Guidelines
Excessive use of calcium and vitamin D in treating hypocalcemia can lead to hypercalcemia, causing symptoms like nausea, vomiting, constipation, confusion, fatigue, muscle weakness, and kidney stones, as reported in a recent study 1. In severe cases, it may result in cardiac arrhythmias, coma, or even death. The kidneys can also be damaged through nephrocalcinosis (calcium deposits in kidney tissue) and nephrolithiasis (kidney stones), potentially leading to chronic kidney disease. Some of the key points to consider include:
- Metastatic calcification can occur when calcium deposits in soft tissues throughout the body, affecting blood vessels, joints, and organs.
- Vitamin D toxicity specifically causes hypercalciuria (excessive calcium in urine), dehydration, and can worsen the hypercalcemia, as noted in a study on vitamin D toxicity 1.
- These complications develop because calcium and vitamin D work together to increase calcium absorption from the intestines and release from bones, while reducing renal excretion.
- When treatment exceeds what's needed to normalize calcium levels, these mechanisms continue to elevate calcium beyond the normal range, resulting in these adverse effects. It is essential to monitor calcium and vitamin D levels closely to avoid these complications, especially in high-risk situations, such as rapid bone remineralization after correction of hyperparathyroid bone disease, as highlighted in a study on chronic kidney disease-mineral and bone disorder 1.
From the Research
Causes of Excessive Use of Calcium and Vitamin D in Hypocalcemia Treatment
- The excessive use of calcium and vitamin D in the treatment of hypocalcemia can lead to hypercalcemia, a condition characterized by elevated serum calcium levels 2, 3, 4.
- Hypercalcemia can cause a range of symptoms, including nausea, vomiting, dehydration, confusion, somnolence, and coma, particularly in severe cases 2, 3.
- The use of calcium and vitamin D supplements can lead to hypercalcemia, especially in susceptible individuals, such as those with renal insufficiency or metabolic alkalosis 4.
Characteristics of Hypercalcemia Induced by Calcium Intake
- Hypercalcemia induced by calcium intake, also known as "calcium supplement syndrome," is characterized by hypercalcemia, normal parathyroid hormone (PTH) level, renal insufficiency, metabolic alkalosis, and a history of calcium intake 4.
- The diagnosis of calcium supplement syndrome is based on the presence of these characteristics, as well as documented improvement with treatment 4.
Treatment of Hypercalcemia and Hypocalcemia
- The treatment of hypercalcemia typically involves correcting dehydration, improving kidney function, lowering calcium levels, and decreasing osteoclastic bone resorption 2, 3.
- In contrast, the treatment of hypocalcemia typically involves oral calcium and vitamin D supplementation, as well as intravenous calcium infusion in acute cases 5, 6.
- In patients with hypoparathyroidism, recombinant human parathyroid hormone (rhPTH) therapy may be used to correct serum calcium levels and reduce the need for calcium and vitamin D supplements 6.