Minor
Calcium carbonate × Colecalciferol
Mineral supplements. Calcium×Vitamins. Regulator of calcium-phosphorus metabolism
Mechanism
Vitamin D increases intestinal calcium absorption by activating calbindin in enterocytes. The synergistic effect benefits osteoporosis and calcium deficiency.
Symptoms
On a balanced dose, no symptoms. At excessive doses of vitamin D (over 4000 IU/day chronically) and calcium (over 1500 mg/day), hypercalcaemia risk: thirst, polyuria, nausea, weakness, arrhythmia.
Management
Standard combination in osteoporosis prevention and treatment: colecalciferol 800–2000 IU/day plus calcium 1000–1200 mg/day (counting dietary calcium). Check calcium and creatinine every 6 months in patients with chronic kidney disease or prior nephrolithiasis.