Rocaltrol Special Precautions

General: There is a close correlation between treatment with calcitriol and the development of hypercalcemia. An abrupt increase in calcium intake as a result of changes in diet (e.g. increased consumption of dairy products) or uncontrolled intake of calcium preparations may trigger hypercalcemia. Patients and their families should be advised that strict adherence to the prescribed diet is mandatory and they should be instructed on how to recognise the symptoms of hypercalcemia. As soon as the serum calcium levels rise to 1 mg/100 ml (250 μmol/l) above normal (9-11 mg/100 ml, or 2250-2750 μmol/l), or serum creatinine rises to >120 μmol/l, treatment with Calcitriol (Rocaltrol) should be stopped immediately until normocalcemia ensues (see Dosage & Administration).
Immobilized patients, e.g. those who have undergone surgery, are particularly exposed to the risk of hypercalcemia.
Calcitriol increases inorganic phosphate levels in serum. While this is desirable in patients with hypophosphatemia, caution is called for in patients with renal failure because of the danger of ectopic calcification. In such cases, the plasma phosphate level should be maintained at the normal level (2-5 mg/100 ml or 0.65-1.62 mmol/l) by the oral administration of appropriate phosphate-binding agents and low phosphate diet.
The serum calcium times phosphate (Ca x P) product should not be allowed to exceed 70 mg²/dl².
Patients with vitamin D-resistant rickets (familial hypophosphatemia) who are being treated with Calcitriol (Rocaltrol) must continue their oral phosphate therapy. However, possible stimulation of intestinal absorption of phosphate by Calcitriol (Rocaltrol) should be taken into account since this effect may modify the need for phosphate supplementation.
Since calcitriol is the most effective vitamin D metabolite available, no other vitamin D preparation should be prescribed during treatment with Calcitriol (Rocaltrol), thereby ensuring that the development of hypervitaminosis D is avoided. If the patient is switched from ergocalciferol (vitamin D₂) to calcitriol, it may take several months for the ergocalciferol level in the blood to return to the baseline value (see Overdosage).
Patients with normal renal function who are taking Calcitriol (Rocaltrol) should avoid dehydration. Adequate intake should be maintained.
Laboratory Tests: The regular laboratory investigations that are required include serum determinations of calcium, phosphorus, magnesium and alkaline phosphatase and of the calcium and phosphate content in 24-hour urine. During the stabilization phase of treatment with Calcitriol (Rocaltrol), serum calcium levels should be checked at least twice weekly (see Dosage & Administration).
Ability to Drive and Use Machines: On the basis of the pharmacodynamic profile of reported adverse events, this product is presumed to be safe or unlikely to adversely affect such activities.
Renal Impairment: See Special Dosage Instructions under Dosage & Administration.
Use in Children: See Special Dosage Instructions under Dosage & Administration.
Use in the Elderly: See Special Dosage Instructions under Dosage & Administration.