causes of hypercalcemia Causes of hypercalcemia include malignancy hypercalcemia in malignancy caused by parathyroid-related hormone protein (PTHrP) characterized by: hypercalcemia, hypophosphatemia, low PTH examples of malignancies: Paget's Disease Multiple Myeloma Squamous cell cancer of the lung ectopic production of PTH Multiple endocrine neoplasia (type I and II) Pituitary adenoma medical conditions primary hyperparathyroidism sarcoidosis Familial hypocalciuric hypercalcemia hyperthyroidism Addison's disease Zollinger-Ellison syndrome drugs thiazide diuretics dietary calcium ingestion (milk-alkali syndrome) hypervitaminosis D hypervitaminosis A Presentation Symptoms CNS confusion stupor weakness gastrointestinal constipation anorexia nausea vomiting kidney polyuria kidney stones polydipsia Treatment Hydration saline diuresis Drug therapies loop diuretics bisphosphonates mithramycin calcitonin galium nitrate Dialysis (severe)