<p>Hypercalcemia (e.g. in hyperparathyroidism, vitamin-D overdosage, decalcifying tumors such as plasmocytoma, bone metastases); severe hypercalciuria; severe renal failure.<br />
<br />
Patients with hyperoxalauria, glucose-6- phosphate dehydrogenase deficiency, or iron overload. Larger doses may lead to gastrointestinal tract upset.</p>