Page 1047 - Basic _ Clinical Pharmacology ( PDFDrive )

CHAPTER 57 Heavy Metal Intoxication & Chelators 1033

thalassemia. Compared to deferasirox, deferiprone appears to be PREP AR A TIONS
relatively more efficient in decreasing cardiac iron but less efficient A V AIL ABLE
in decreasing hepatic iron. Because neutropenia has occurred in
5–10% of patients, with agranulocytosis in approximately 1%,
regular hematologic monitoring is recommended. GENERIC NAME AVAILABLE AS
Magnetic resonance imaging has been increasingly used to Deferasirox Exjade, Jadenu
evaluate cardiac and hepatic iron burden and to guide iron chelation Deferiprone Ferriprox
therapy. Regimens that combine iron-chelating agents have been Deferoxamine Generic, Desferal
used in cases when monotherapy has yielded suboptimal results. Dimercaprol BAL in Oil
Edetate calcium [calcium EDTA] Calcium Disodium Versenate
Penicillamine Cuprimine, Depen
PRUSSIAN BLUE (FERRIC Pentetate Calcium Trisodium Generic
HEXACYANOFERRATE) [calcium DTPA] and Pentetate Zinc
Trisodium [zinc DTPA]
Prussian Blue Radiogardase
Ferric hexacyanoferrate (insoluble Prussian blue) is a hydrated Succimer Chemet, Succicaptal (in Europe)
3+
2+
crystalline compound in which Fe and Fe atoms are coordi- Unithiol Dimaval
nated with cyanide groups in a cubic lattice structure. Although
used as a dark blue commercial pigment for nearly 300 years, it
was only three decades ago that its potential usefulness as a phar-
maceutical chelator was recognized. Primarily by ion exchange, REFERENCES
and secondarily by mechanical trapping or adsorption, the com- Lead
pound has high affinity for certain univalent cations, particularly Advisory Committee on Childhood Lead Poisoning Prevention of the Centers for
cesium and thallium. Used as an oral drug, insoluble Prussian blue Disease Control and Prevention. Low Level Lead Exposure Harms Children:
undergoes minimal gastrointestinal absorption (<1%). Because A Renewed Call for Primary Prevention. CDC: Atlanta, GA. 2012. http://
the complexes it forms with cesium or thallium are nonabsorb- www.cdc.gov/nceh/lead/ACCLPP/Final_Document_030712.pdf.
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associated with a decline in the biologic half-life (ie, in vivo reten- exposure. J Environ Sci Health Part A 2009;44:1200.
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and Management of Lead Exposure in Pregnant and Lactating Women. CDC,
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Indications & Toxicity Environmental Protection Agency. Integrated Science Assessment for Lead. EPA:
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In 2003, the FDA approved Prussian blue for the treatment of Kosnett MJ et al: Recommendations for medical management of adult lead expo-
137
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soluble forms of Prussian blue, such as potassium ferric hexacya- Arsenic
noferrate, may have better utility in thallium poisoning, only the
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After exposure to 137 Cs or thallium salts, the approved adult nic methylation and implications for disease susceptibility. Environ Res
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137
( Cs) and urinary thallium concentrations can guide the recom- James KA et al: Association between lifetime exposure to inorganic arsenic in
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137
sible acute radiation illness ( Cs) or systemic thallium toxicity National Research Council: Critical Aspects of EPA’s IRIS Assessment of Inorganic
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effects. Constipation, which may occur in some cases, should be Naujokas MF et al: The broad scope of health effects from chronic arsenic
exposure: Update on a worldwide public health problem. Environ Health
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