Chelating agents edetate calcium disodium

Comments used in pharmaceutical formulations as a chelating agent in concentrations between 0.01-0.1% w/v. Usually edetate calcium disodium is used in pharmaceutical formulations in preference to disodium edetate or sodium edetate to prevent calcium depletion occurring in the body. In food products, edetate calcium disodium may also be used in flavors and as a color retention agent. Edetate calcium disodium occurs as the dihydrate, trihydrate, and anhydrous material. 

A number of natural substances, including sodium citrate and ascorbic acid, chelate Pb. Commonly used chelating agents include calcium disodium edetate (CaEDTA), dimercaprol (BAL), 2,2-dimethylcysteine (D-peniciUamine) and 2,3-dimercaptosuc-cinic acid (DMS). Chisholm and Coffin et al." have outlined the appropriate protocols for chelation therapy for children wdth Pb poisoning, whereas Friedheim et al. and the Center for Disease Control, outline the treatment of adult Pb intoxication. 

Chelating agents such as disodium edetate (EDTA) are commonly used in lens care products to enhance the antimicrobial activity of preservatives and remove calcium and magnesium from the lens. EDTA is the most... 

Edetic acid and edetate salts are used in pharmaceutical formulations, cosmetics, and foods as chelating agents. They form stable water-soluble complexes (chelates) with alkaline earth and heavy metal ions. The chelated form has few of the properties of the free ion, and for this reason chelating agents are often described as removing ions from solution this process is also called sequestering. The stability of the metal-edetate complex depends on the metal ion involved and also on the pH. The calcium chelate is relatively weak and will preferentially chelate heavy metals, such as iron, copper, and lead, with the release of calcium ions. For this reason, edetate calcium disodium is used therapeutically in cases of lead poisoning see also Section 18. 

Medical treatment with chelation uses four different agents British Anti-Lewisite (2,3-dimercaptopropanol), edetate calcium disodium, D-penicillamine, and succimer or meso-2,3-dimercaptosuccinic acid (Roper et al. 1993). British Anti-Lewisite is contraindicated in children allergic to peanuts and in glucose-6-phosphate dehydrogenase deficiency D-penicillamine is contraindicated in penicillin allergy (Roper et al. 1993). 

Edetate calcium disodium, a metal-chelating agent, is indicated in the treatment of symptomatic lead poisoning without encephalopathy and blood lead concentrations less than 100 mcg/dL, or in the treatment of severe lead poisoning with symptoms of encephalopathy and/or blood lead concentrations greater than 100 mcg/dL. 

EDTA, its sodium salt (edetate disodium, Na2EDTA), and a number of closely related compounds chelate many divalent and trivalent metals. The cation used to make a water-soluble salt of EDTA has an important role in the toxicity of the chelator. Na2EDTA causes hypocalcemic tetany. However, edetate calcium disodium (CaNa2EDTA) can be used for treatment of poisoning by metals that have higher affinity for the chelating agent than does Ca. ... 

Because the onset of lead poisoning usually is insidious, it often is desirable to estimate the body burden of lead in individuals who are exposed to an environment that is contaminated with the metal. In the past, the edetate calcium disodium (CaNaJlDTA) provocation test was used to determine whether there is an increased body burden of lead in those for whom exposure occurred much earlier. The provocation test is performed by intravenous administration of a single dose of CaNa DTA (50 mg/kg) followed by collection of urine for 8 hours. The test is positive for children when the lead excretion ratio (pg of lead excreted in the urine per mg of CaNa DTA administered) is >0.6 it also may be useful for therapeutic chelation in children with blood levels of 25 5 pg/dL. This test is not used in symptomatic patients or in those whose concentration of lead in blood is >45 pg/dL because these patients require the proper therapeutic regimen with chelating agents (see below). 

The health-care provider has prescribed edetate calcium disodium (Calcium EDTA), a chelating agent, for a child diagnosed with lead poisoning. Which intervention should the nurse implement ... 

Di-Na monO Ca salt [62-33-9]. Sodium calcium edetate, BAN, INN. Edetate calcium disodium, USAN. Edathamil calcium disodium. Calcium disodium versenate. Mosatil. Antallin. Ledclair. Other proprietary names Powerful chelating agent used for treatment of lead poisoning. Powder. Forms a tetrahydrate. 

Corneal band keratopathy Edetate disodium (disodium EDTA Endrate) is a chelating agent that can be used to remove a band keratopathy (i.e., a calcium deposit at the level of Bowman s membrane on the cornea). After the overlying corneal epithelium is removed, it is applied topically to chelate the calcium deposits from the cornea. 

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