Interactions : אינטראקציות

4.5 Interaction with other medicinal products and other forms of interaction

No interaction studies have been performed with paricalcitol injection. However, an interaction study between ketoconazole and paricalcitol has been performed with the capsule formulation.
Ketoconazole: Ketoconazole is known to be a non-specific inhibitor of several cytochrome P450 enzymes. The available in vivo and in vitro data suggest that ketoconazole may interact with enzymes that are responsible for the metabolism of paricalcitol and other vitamin D analogs. Caution should be taken while dosing paricalcitol with ketoconazole (see section 4.4). The effect of multiple doses of ketoconazole administered as 200 mg, twice daily (BID) for 5 days on the pharmacokinetics of paricalcitol capsule has been studied in healthy subjects. The Cmax of paricalcitol was minimally affected, but AUCₒ­∞ approximately doubled in the presence of ketoconazole. The mean half-life of paricalcitol was 17.0 hours in the presence of ketoconazole as compared to 9.8 hours, when paricalcitol was administered alone. The results of this study indicate that following oral administration of paricalcitol the maximum amplification of the paricalcitol AUC∞ from a drug interaction with ketoconazole is not likely to be greater than about two-fold.
Specific interaction studies were not performed with paricalcitol injection. Digitalis toxicity is potentiated by hypercalcaemia of any cause, so caution should be applied when digitalis is prescribed concomitantly with paricalcitol (see section 4.4).
Phosphate or vitamin D-related medicinal products should not be taken concomitantly with paricalcitol, due to an increased risk of hypercalcaemia and Ca x P product elevation (see section 4.4).
High doses of calcium-containing preparations or thiazide diuretics may increase the risk of hypercalcaemia.
Magnesium-containing preparations (e.g., antacids) should not be taken concomitantly with vitamin D preparations, because hypermagnesaemia may occur.
Aluminium-containing preparations (e.g., antacids, phosphate-binders) should not be administered chronically with Vitamin D medicinal products, as increased blood levels of aluminum and aluminum bone toxicity may occur.