THERE IS AN INCREASED RISK OF HYPERCALCAEMIA IF ALFACALCIDOL IS COADMINISTERED WITH THIAZIDE DIURETICS AND CALCIUM. SOME ANTIEPILEPTICS MAY INCREASE ALFACALCIDOL REQUIREMENTS (SUCH AS CARBAMAZEPINE, PHENOBARBITONE, PHENYTOIN, AND PRIMIDONE). DANAZOL APPEAR TO REDUCE THE MAINTENANCE DOSE OF ALFACALCIDOL.