Calcium supplements Avoid uncontrolled intake of additional calcium-containing preparations.
Cholestyramine May reduce intestinal absorption of fat soluble vitamins.
Ketoconazole May reduce endogenous calcitriol concentrations.
Magnesium Magnesium-containing products may cause hypermagnesemia and should be avoided during calcitriol administration to patients on chronic renal dialysis.
Phenytoin/Phenobarbital Inhibits endogenous synthesis of calcitriol, therefore may require higher doses if given simultaneously.
Phosphate-binding agents Because phosphate transport in the intestine, kidneys, and bones may be affected, the dosage of phosphate-binding agents must be adjusted based on serum phosphate concentration.
Thiazides Known to induce hypercalcemia by the reduction of calcium excretion.
Vitamin D To avoid possible additive effects and hypercalcemia, withhold pharmacologic doses of vitamin D and its derivatives.
|