Pamidronate sodium

Common Name Dinatrium pamidronat Disodium pamidronate Pamidronate sodium... 

Bone pain, including cancer metastases, requires NSAIDs alone and with opioids. Bisphosphonates, e.g. sodium pamidronate, sodium clodronate, relieve pain from osteolytic bone metastases from breast cancer and multiple myeloma. 

Pamidronate, a second-generation bisphosphonate, is 100-fold more potent than etidronate (Fig. 35.7) (6). It has been approved for the treatment of hypercalcemia of malignancy, for Paget s disease, and for osteolytic bone metastases of breast cancer and osteolytic lesions of multiple myeloma. When used to treat bone metastases, pamidronate decreases osteoclast recruitment, decreases osteoclast activity and increases osteoclast apoptosis (53). Erosive esophagitis has been reported with the use of pamidronate sodium. 

C3H7NO2 107-95-9) see Balsalazide sodium Calcium pantothenate Pamidronic acid L-alanine benzyl ester... 

Bisphosphonates alendronate sodium clodronate disodium etidronate disodium pamidronate disodium risedronate sodium zoledronic acid... 

Giving intravenous phosphate is probably the fastest and surest way to reduce serum calcium, but it is a hazardous procedure if not done properly. Intravenous phosphate should be used only after other methods of treatment (pamidronate, calcitonin, saline diuresis with furosemide, and plicamycin) have failed to control symptomatic hypercalcemia. Phosphate must be given slowly (50 mmol or 1.5 g elemental phosphorus over 6-8 hours) and the patient switched to oral phosphate (1-2 g/d elemental phosphorus, as one of the salts indicated below) as soon as symptoms of hypercalcemia have cleared. The risks of intravenous phosphate therapy include sudden hypocalcemia, ectopic calcification, acute renal failure, and hypotension. Oral phosphate can also lead to ectopic calcification and renal failure if serum calcium and phosphate levels are not carefully monitored, but the risk is less and the time of onset much longer. Phosphate is available in oral and intravenous forms as the sodium or potassium salt. Amounts required to provide 1 g of elemental phosphorus are as follows ... 

For a batch size of 5 L, 587.5 g (3.2 moles) of mannitol is dissolved in 3.5 L of water. Pamidronic acid (31.6 g, 0.133 moles) is mixed with a 1.0 L aliquot of the mannitol solution to form a slurry. The slurry is then transferred into the remainder of the mannitol solution, and stirred for at least 15 min. Aqueous 1 N sodium hydroxide (270 ml) is then added and the mixture is stirred until a clear, colorless solution results. The pH is then adjusted to 6.50.1 using either 1 M aqueous phosphoric acid or 1 N aqueous sodium hydroxide, as needed. The solution is then filtered through a 0.22 micron filter, and filled at 20°C into vials at 4.0 ml (4.172 g)/vial, under sterile conditions. The aqueous solution is frozen at -37°C and lyophilized (20 mbar, 20°-40°C) to yield 1,250 vials, each containing 30 mg of amorphous disodium pamidronate. The vials are sealed under positive nitrogen pressure. The disodium pamidronate is amorphous (noncrystalline) by X-ray diffraction and contains 0.7 wt-% water. 

The treatment of Mrs CR s hypercalcaemia is urgent and requires immediate administration of bisphosphonate therapy, the first choice therapy in cases of severe hypercalcaemia. Currently four bisphosphonates are available in the UK for the treatment of malignant hypercalcaemia - sodium clodronate, disodium pamidronate, zoledronic acid and ibandronic acid. The choice of which bisphosphonate to recommend will depend on which one is on the local hospital formulary. 

Weidenauer, U., Bodmeier, D., and Kissel,T. (2003), Microencapsulation of hydrophilic drug substances using biodegradable polyesters. Part I Evaluation of different techniques for the encapsulation of pamidronate di-sodium salt, J. Microencapsul., 20, 509-524. 

Several bisphosphonates are available in the United States. Etidronate sodium (Didronel) is used for treatment of Paget s disease and may be used parenteraUy to treat hypercalcemia. Because etidronate is the only bisphospho-nate that inhibits mineralization, it has been supplanted largely by pamidronate and zoledronate for treating hypercalcemia. Pamidronate (Aredia) is approved for management of hypercalcemia but also is effective in other... 

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