Lead poisoning, treatment

Lead poisoning Treatment of lead poisoning in children with blood lead levels above 45 mcg/dL. Not indicated for prophylaxis of lead poisoning in a lead-containing environment always accompany succimer use with identification and removal of the source of lead exposure. 

Medical Uses. A significant usage of chelation is in the reduction of metal ion concentrations to such a level that the properties may be considered to be negligible, as in the treatment of lead poisoning. However, the nuclear properties of metals may retain then full effect under these conditions, eg, in nuclear magnetic resonance or radiation imaging and in localizing radioactivity. 

Full Fanconi syndrome has been reported to be present in some children with lead encephalopathy (Chisolm 1968 Chisolm et al. 1955). According to the National Academy of Sciences (NAS 1972), the Fanconi syndrome is estimated to occur in approximately one out of three children with encephalopathy and PbB levels of approximately 150 pg/dL. Aminoaciduria occurs at PbB levels >80 pg/dL in children with acute symptomatic lead poisoning (Chisolm 1962). The aminoaciduria and symptoms of lead toxicity disappeared after treatment with chelating agents (Chisolm 1962). 

Kohler PF Tulane University School of Medicine, New Orleans, LA To determine lead poisoning process to evaluate the use of the oral chelator of lead, Succimer, in the diagnosis and treatment of lead poisoning in adults National Center for Research Resources ... 

Angle CR. 1993. Childhood lead poisoning and its treatment. Ann Rev Pharmacol Toxicol 33 409-434. 

Batuman V, Wedeen RP, Bogden JD, et al. 1989. Reducing bone lead content by chelation treatment in chronic lead poisoning An in vivo X-ray fluorescence and bone biopsy study. Environ Res 48 70-75. 

Degemes, L.A., P.T. Redig, and M.L. Freeman. 1990. Treatment of lead poisoning in trumpeter swans (Cygnus buccinator). Pages 15-20 in D.R. Ludwig (ed.). Wildlife Rehabilitation. Vol. 8. Eighth Sympos. Natl. Wildl. Rehab. Assoc., 21-25 March 1990, Ithaca, NY. 

Murase, T., N. Horiba, I. Goto, O. Yamato, T. Ikeda, K. Sato. 1993. Erythrocyte ALA-d activity in experimentally lead-poisoned ducks and its change during treatment with disodium calcium EDTA. Res. Veterin. Sci. 55 252-257. 

Sears, J., S.W. Cooke, Z.R. Cooke, and TJ. Heron. 1989. A method for the treatment of lead poisoning in the mute swan (Cygnus olor) and its long-term success. Brit. Veterin. Jour. 145 586-595. 

Sill, F.G., J.P. Reyes, J.R. Lezama, E.A. Fernandez, R. Rosiles, and J. Bautista. 1996. Treatment of balantidiasis in lowland gorillas and a case complicated with salmonellosis and lead poisoning. Proc. Amer. Assoc. Zoo. Veterin. 1996 410-417. 

For the treatment of poisoning, a selective antidote (which antagonises the action) may be given e.g., nalorphine and naloxone in case of morphine poisoning, atropine in case of anticholinergic drugs, dimercaprol in mercury and penicillamine in lead poisoning, etc. 

Dimercaprol is FDA-approved as single-agent treatment of acute poisoning by arsenic and inorganic mercury and for the treatment of severe lead poisoning when used in conjunction with edetate calcium disodium (EDTA see below). Although studies of its metabolism in humans are limited, intramuscularly administered dimercaprol appears to be readily absorbed, metabolized, and excreted by the kidney within 4-8 hours. Animal models indicate that it may also undergo biliary excretion, but the role of this excretory route in humans and other details of its biotransformation are uncertain. 

Higher concentrations of a chemical entity may cause a pharmacological response whereas lower concentrations are incapable of doing so. For example, edetate calcium disodium (9) at a formulated concentration of 20% is indicated as a drug for the treatment of lead poisoning and lead encephalopathy while it can be found commonly present as an excipient in concentrations ranging from 0.01% to 0.1% in parenteral formulations to prevent oxidation of the active ingredient. 

The treatment of lead poisoning involves the use of chelating agents to remove the lead from the soft tissues of the body. Thus, agents such as sodium calcium edetate may be used. 

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