Regulation of Calcium Homeostasis

* Actions: Vitamin D3 and D2 analogs respectively
* Uses: Prevention/treatment of osteomalacia and rickets

* Action: Active form of vitamin D
* Uses: Hypoparathyroidism, hypocalcemia, osteomalacia, rickets, renal disease
* AR: HYPERCALCEMIA,

* Action: Ca++ receptor (CaR) activator; allosteric modulation of Ca++ receptor enhancing response to Ca++ resulting in decreased PTH release
* AR: HYPOCALCEMIA
* Uses: 2ndary hyperparathyroidism of CHRONIC KIDNEY DISEASE and PARATHYROID CARCINOMA...also used in DIALYSIS b/c the drug is highly protein-bound

* Action: Chelates Ca++ targeting remodeling bone surface; incorporated into bone, difficult to resorb
* AR: Esophageal irritation, osteonecrosis, flu-like symptoms
* CI: Renal impairment when drug will accumulate
* Uses: Conditions of high bone turnover

* Action: Chelates Ca++ targeting remodeling bone surface; incorporated into bone, difficult to resorb
* AR: Esophageal irritation, osteonecrosis, flu-like symptoms
* CI: Renal impairment when drug will accumulate
* Uses: Hypercalcemia of MALIGNANCY or Paget's disease of the bone

* Uses: Constrain bone loss in those with hypercalciuria

* Action: Binds intestinal PO42- preventing absorption and decreasing serum PO42- levels
* AR: GI symptoms
* Uses: Patients w/ renal failure or dialysis