<p>Digitalis; ketoconazole &amp; other strong P450 3A inhibitors including atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole. May interfere absorption with cholestyramine (cap only). Increased risk of hypercalcemia with prescription-based phosphate or vit D-related medicinal products &amp; Ca-containing prep or thiazide diuretics. Mg- &amp; Al-containing prep (eg, antacids, phosphate-binders).</p>