Calcitriol

Predialysis Patients Calcitriol Oral Solution is indicated in the management of secondary hyperparathyroidism and resultant metabolic bone disease in patients with moderate to severe chronic renal failure (Ccr 15 to 55 mL/min) not yet on dialysis. In children, the creatinine clearance value must be corrected for a surface area of 1.73 square meters. A serum iPTH level of ≥ 100 pg/mL is strongly suggestive of secondary hyperparathyroidism. Dialysis Patients Calcitriol Oral Solution is indicated in the management of hypocalcemia and the resultant metabolic bone disease in patients undergoing chronic renal dialysis. …

• The optimal daily dose of Calcitriol Oral Solution must be carefully determined for each patient
• Calcitriol Oral Solution can be administered as an oral solution (1 mcg/mL)
• Calcitriol Oral Solution therapy should always be started at the lowest possible dose and should not be increased without careful monitoring of serum calcium
• The effectiveness of Calcitriol Oral Solution therapy is predicated on the assumption that each patient is receiving an adequate but not excessive daily intake of calcium
• Patients are advised to have a dietary intake of calcium at a minimum of 600 mg daily
• The U.S
• RDA for calcium
• In adults is 800 mg to 1200 mg
• To ensure that each patient receives an adequate daily intake of calcium, the physician should either prescribe a calcium supplement or instruct the patient in proper dietary measures
• Because of improved calcium absorption from the gastrointestinal tract, some patients on Calcitriol Oral Solution may be maintained on a lower calcium intake
• Patients who tend to develop hypercalcemia may require only low doses of calcium or no supplementation at all
• During the titration period of treatment with Calcitriol Oral Solution, serum calcium levels should be checked at least twice weekly
• When the optimal dosage of Calcitriol Oral Solution has been determined, serum calcium levels should be checked every month (or as given below for individual indications)
• Samples for serum calcium estimation should be taken without a tourniquet

• Calcitriol Oral Solution should not be given to patients with hypercalcemia or evidence of vitamin D toxicity
• Use of Calcitriol Oral Solution in patients with known hypersensitivity to Calcitriol Oral Solution (or drugs of the same class) or any of the inactive ingredients is contraindicated

Overdosage of any form of vitamin D is dangerous (see OVERDOSAGE ). Progressive hypercalcemia due to overdosage of vitamin D and its metabolites may be so severe as to require emergency attention. Chronic hypercalcemia can lead to generalized vascular calcification, nephrocalcinosis and other soft-tissue calcification. The serum calcium times phosphate (Ca x P) product should not be allowed to exceed 70 mg 2 /dL 2 . Radiographic evaluation of suspect anatomical regions may be useful in the early detection of this condition. Calcitriol Oral Solution is the most potent metabolite of vitamin D available. …

Since Calcitriol Oral Solution is believed to be the active hormone which exerts vitamin D activity in the body, adverse effects are, in general, similar to those encountered with excessive vitamin D intake, ie, hypercalcemia syndrome or calcium intoxication (depending on the severity and duration of hypercalcemia) (see WARNINGS ). Because of the short biological half-life of calcitriol, pharmacokinetic investigations have shown normalization of elevated serum calcium within a few days of treatment withdrawal, ie, much faster than in treatment with vitamin D 3 preparations. …

Administration of Calcitriol Oral Solution to patients in excess of their daily requirements can cause hypercalcemia, hypercalciuria, and hyperphosphatemia. Since calcitriol is a derivative of vitamin D, the signs and symptoms of overdose are the same as for an overdose of vitamin D (see ADVERSE REACTIONS ). High intake of calcium and phosphate concomitant with Calcitriol Oral Solution may lead to similar abnormalities. The serum calcium times phosphate (Ca x P) product should not be allowed to exceed 70 mg 2 /dL 2 . …

Take it when you remember, unless it is nearly time for the next dose. Then skip the missed one. Never take two doses at once to make up for it. Check your leaflet, as some medicines are different.