Paricalcitol - Warnings and Precautions

5 WARNINGS AND PRECAUTIONS Excessive administration of vitamin D compounds, including ZEMPLAR capsules, can cause over suppression of PTH, hypercalcemia, hypercalciuria, hyperphosphatemia, and adynamic bone disease.

Hypercalcemia: Excessive administration of ZEMPLAR capsules can cause over suppression of PTH, hypercalcemia, hypercalciuria, hyperphosphatemia, and adynamic bone disease.

Prescription-based doses of vitamin D and its derivatives should be withheld during ZEMPLAR treatment .

Digitalis toxicity: Potentiated by hypercalcemia of any cause.

Use caution when ZEMPLAR capsules are prescribed concomitantly with digitalis compounds .

Laboratory tests: Monitor serum calcium, serum phosphorus, and serum or plasma iPTH during initial dosing or following any dose adjustment.

ZEMPLAR capsules may increase serum creatinine and therefore decrease the estimated GFR (eGFR) .

Aluminum overload and toxicity: Avoid excessive use of aluminum containing compounds .

5.1 Hypercalcemia Progressive hypercalcemia due to overdosage of vitamin D and its metabolites may be so severe as to require emergency attention [see Overdosage ] .

Acute hypercalcemia may exacerbate tendencies for cardiac arrhythmias and seizures and may potentiate the action of digitalis.

Chronic hypercalcemia can lead to generalized vascular calcification and other soft-tissue calcification.

Concomitant administration of high doses of calcium-containing preparations or thiazide diuretics with ZEMPLAR may increase the risk of hypercalcemia.

High intake of calcium and phosphate concomitant with vitamin D compounds may lead to serum abnormalities requiring more frequent patient monitoring and individualized dose titration.

Patients also should be informed about the symptoms of elevated calcium, which include feeling tired, difficulty thinking clearly, loss of appetite, nausea, vomiting, constipation, increased thirst, increased urination and weight loss.

Prescription-based doses of vitamin D and its derivatives should be withheld during ZEMPLAR treatment to avoid hypercalcemia.

5.2 Digitalis Toxicity Digitalis toxicity is potentiated by hypercalcemia of any cause.

Use caution when ZEMPLAR capsules are prescribed concomitantly with digitalis compounds.

5.3 Laboratory Tests During the initial dosing or following any dose adjustment of medication, serum calcium, serum phosphorus, and serum or plasma iPTH should be monitored at least every two weeks for 3 months, then monthly for 3 months, and every 3 months thereafter.

In pre-dialysis patients, ZEMPLAR capsules may increase serum creatinine and therefore decrease the estimated GFR (eGFR).

Similar effects have also been seen with calcitriol.

5.4 Aluminum Overload and Toxicity Aluminum-containing preparations (e.g., antacids, phosphate binders) should not be administered chronically with ZEMPLAR, as increased blood levels of aluminum and aluminum bone toxicity may occur.