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{{short description|Medical procedure to remove heavy metals from the body}} | |||
'''Chelation therapy''' is the administration of ]s to remove ] from the body. For the most common forms of heavy metal intoxication—those involving ], ] or ]—the ] in the USA dictates the use of ] (DMSA) or ].{{Fact|date=May 2008}} Other ], such as ] (DMPS) and ] (ALA), are used in ] and ]. | |||
{{Infobox medical intervention | |||
| name = Chelation therapy | |||
| image = Deferasirox–iron(III) complex.png | |||
| caption = Two molecules of ], an orally administered chelator, binding ]. Deferasirox is used in the treatment of ] in people with ]. | |||
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'''Chelation therapy''' is a medical procedure that involves the administration of ] agents to remove ] from the body.<ref name=crisponi>{{cite book | |||
|first1= Jan|last1= Aaseth|first2=Guido|last2=Crisponi|first3=Ole|last3=Anderson|title= Chelation Therapy in the Treatment of Metal Intoxication | |||
|year=2016|publisher=Academic Press|page=388| isbn =978-0-12-803072-1}}</ref> Chelation therapy has a long history of use in clinical ]<ref>{{cite web|url=http://www.poison.org/current/chelationtherapy.htm|title=Chelation: Therapy or "Therapy"? |date= 6 May 2013 |orig-date= 2010 |publisher= National Capital Poison Center |work= poison.org |access-date=9 October 2013}}</ref> and remains in use for some very specific medical treatments, although it is administered under very careful medical supervision due to various inherent risks, including the mobilization of mercury and other metals through the brain and other parts of the body by the use of weak chelating agents that unbind with metals before elimination, exacerbating existing damage.<ref name=Atwood2008>{{cite journal |last1= Atwood |first1= K.C. IV |author-link1= Kimball Atwood |last2= Woeckner |first2= E. |last3= Baratz |first3= R.S. |author3-link= Robert Baratz |last4= Sampson |first4= W.I. |author4-link= Wallace Sampson |title=Why the NIH Trial to Assess Chelation Therapy (TACT) should be abandoned |journal= Medscape Journal of Medicine |volume=10 |issue=5 |page=115 |year=2008 |pmid=18596934 |pmc=2438277 }}</ref> To avoid mobilization, some practitioners of chelation use strong chelators, such as ], taken at low doses over a long period of time. | |||
Chelation therapy must be administered with care as it has a number of possible side effects, including death.<ref name="acs">{{cite web|title=Chelation Therapy|url=http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/pharmacologicalandbiologicaltreatment/chelation-therapy|date=1 November 2008|publisher=]|archive-url=https://web.archive.org/web/20100705115407/http://www.cancer.org/treatment/treatmentsandsideeffects/complementaryandalternativemedicine/pharmacologicalandbiologicaltreatment/chelation-therapy|archive-date=5 July 2010|access-date=14 September 2013}}</ref><ref>{{Cite web|url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5508a3.htm|title=Deaths Associated with Hypocalcemia from Chelation Therapy - Texas, Pennsylvania, and Oregon, 2003-2005|website=www.cdc.gov|access-date=2016-10-13}}</ref> In response to increasing use of chelation therapy as ] and in circumstances in which the therapy should not be used in conventional medicine, various health organizations have confirmed that medical evidence does not support the effectiveness of chelation therapy for any purpose other than the treatment of heavy metal poisoning.<ref name=acs/> Over-the-counter chelation products are not approved for sale in the United States.<ref name="FDA_2010_warning">{{cite press release|url=https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm229320.htm|title=FDA issues warnings to marketers of unapproved 'chelation' products|author=] (FDA)|date=14 October 2010|archive-url=https://wayback.archive-it.org/7993/20170111123610/http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm229358.htm|archive-date=January 11, 2017}}</ref> | |||
== Discovery and history in medicine == | |||
{{Unreferencedsection|date=February 2008}} | |||
Chelating agents were introduced into medicine as a result of the use of ]. The first widely used chelating agent—the organic dithiol compound ], also named British Anti-Lewisite or BAL—was used as an antidote to the arsenic-based poison gas, ]. The sulphur atoms in BAL's ] groups strongly bond to the arsenic in Lewisite, forming a water-soluble compound that entered the bloodstream, allowing it to be removed from the body by the kidneys and liver. BAL had severe side-effects. | |||
== Medical uses == | |||
After World War II, a large number of navy personnel suffered from lead poisoning as a result of their jobs repainting the hulls of ships. The medical use of ] as a lead chelating agent was introduced. Unlike BAL, it is a synthetic ] and contains no mercaptans. While EDTA had some uncomfortable side effects, they were not as severe as BAL. | |||
Chelation therapy is the preferred medical treatment for ],<ref name=crisponi/><ref>{{Cite journal|last1=Flora|first1=Swaran J. S.|last2=Pachauri|first2=Vidhu|date=2010-06-28|title=Chelation in Metal Intoxication|journal=International Journal of Environmental Research and Public Health|language=en|volume=7|issue=12|pages=2745–2788|doi=10.3390/ijerph7072745|pmc=2922724|pmid=20717537|doi-access=free}}</ref> including acute ], ] (including in cases of ] and ]),<ref>{{Cite journal |last1=Fortin |first1=Patricia M. |last2=Fisher |first2=Sheila A. |last3=Madgwick |first3=Karen V. |last4=Trivella |first4=Marialena |last5=Hopewell |first5=Sally |last6=Doree |first6=Carolyn |last7=Estcourt |first7=Lise J. |date=May 8, 2018 |title=Interventions for improving adherence to iron chelation therapy in people with sickle cell disease or thalassaemia |journal=The Cochrane Database of Systematic Reviews |volume=2018 |issue=5 |pages=CD012349 |doi=10.1002/14651858.CD012349.pub2 |issn=1469-493X |pmc=5985157 |pmid=29737522}}</ref><ref>{{cite book | |||
|first1=Robert C. |last1=Hider | |||
|first2=Xiaole |last2=Kong | |||
|editor=Astrid Sigel, Helmut Sigel and Roland K. O. Sigel | |||
|title=Interrelations between Essential Metal Ions and Human Diseases | |||
|series=Metal Ions in Life Sciences | |||
|volume=13 | |||
|year=2013 | |||
|publisher=Springer | |||
|pages=229–294 | |||
|chapter=Chapter 8. Iron: Effect of Overload and Deficiency | |||
|doi=10.1007/978-94-007-7500-8_8 | |||
|pmid=24470094 | |||
|isbn=978-94-007-7499-5 | |||
}}</ref> ], ], ], ] and other forms of ] poisoning. The chelating agent may be administered ], ], or orally, depending on the agent and the type of poisoning.<ref>{{Citation|last1=Flora|first1=Govinder|title=26 - Medical Countermeasures—Chelation Therapy|date=2015-01-01|url=http://www.sciencedirect.com/science/article/pii/B9780124186880000265|work=Handbook of Arsenic Toxicology|pages=589–626|editor-last=Flora|editor-first=S. J. S.|place=Oxford|publisher=Academic Press|language=en|isbn=978-0-12-418688-0|access-date=2020-12-07|last2=Mittal|first2=Megha|last3=Flora|first3=Swaran J. S.}}</ref> | |||
===Chelating agents=== | |||
In the 1960s, BAL was modified into ], a related dithiol with far fewer side effects. DMSA quickly replaced both BAL and EDTA, becoming the US ] for the treatment of lead, arsenic, and mercury poisoning, which it remains today. | |||
There are a variety of common chelating agents with differing affinities for different metals, physical characteristics, and biological ]. For the most common forms of heavy metal intoxication – ], ], or ] – a number of chelating agents are available. ] (DMSA) has been recommended by ]s around the world for the treatment of lead poisoning in children.<ref>{{cite journal |last= Chisolm | first= J.J. Jr. |title=Safety and efficacy of meso-2,3-dimercaptosuccinic acid (DMSA) in children with elevated blood lead concentrations |journal=] |volume=38 |issue=4 |pages=365–75 |year=2000 |pmid=10930052 |doi=10.1081/CLT-100100945 |s2cid= 21793727 }}</ref> Other ], such as ] (DMPS) and ] (ALA), are used in ] and ]. Some common chelating agents are ] (EDTA), 2,3-dimercaptopropanesulfonic acid (DMPS), and ] (TTFD). Calcium-disodium EDTA and DMSA are only approved for the removal of lead by the Food and Drug Administration while DMPS and TTFD are not approved by the FDA. These drugs bind to heavy metals in the body and prevent them from binding to other agents. They are then excreted from the body. The chelating process also removes vital nutrients such as vitamins ] and ], therefore these must be supplemented.<ref>{{cite news |last= Bridges |first= Sarah |date= January 2006 |title= The promise of chelation |magazine= ] |issue= 134 |pages= 54–61}}</ref>{{Unreliable medical source|date=January 2014}} | |||
Research in the former Soviet Union led to the introduction of ], another dithiol, as a mercury-chelating agent. The Soviets also introduced ], which is transformed by the body into the dithiol dihydrolipoic acid, a mercury- and arsenic-chelating agent. DMPS has experimental status in the US FDA, while ALA is a common nutritional supplement. | |||
The German Environmental Agency (]) listed DMSA and DMPS as the two most useful and safe chelating agents available.<ref>{{cite journal |title=Bekanntmachung des Umweltbundesamtes Einsatz von Chelatbildnern in der Umweltmedizin? Stellungnahme der Kommission 'Human-Biomonitoring' des Umweltbundesamtes |trans-title= Notice of the Federal Environmental Agency use of chelating agents in environmental medicine? Opinion of the Commission 'Human biomonitoring' of the German Federal Environment Agency |journal=Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz |volume=42 |issue=10 |pages=823–4 |year=1999 |doi=10.1007/s001030050288 |author= Kommission Human-Biomonitoring des Umweltbundesamtes |s2cid= 30922256 |language= de}}</ref> | |||
Since the 1970s, iron chelation therapy has been used as an alternative to regular ] to treat excess iron stores in people with ].<ref name='CDC_Hemo'> {{cite web|url=http://www.cdc.gov/ncbddd/hemochromatosis/training/treatment/monitoring_treatment.htm |title=Hemochromatosis: Monitoring and Treatment |accessdate=2008-03-29 |date=2007-11-01 |publisher=National Center on Birth Defects and Developmental Disabilities (NCBDDD) }}</ref> | |||
{|class="wikitable" | |||
Other chelating agents have been discovered. They all function by making several chemical bonds with metal ions, thus rendering them much less chemically reactive. The resulting complex is water-soluble, allowing it to enter the bloodstream and be excreted harmlessly. | |||
|- | |||
! Chelator !! Used in | |||
|- | |||
| ] (British anti-Lewisite; BAL) | |||
| | |||
* acute ]<ref name=KatzungTrevor2008>{{cite book |last1=Masters |first1= Susan B. |last2= Trevor |first2= Anthony J. |last3= Katzung |first3= Bertram G. |title=Katzung & Trevor's Pharmacology: Examination & Board Review |publisher= ] |edition= 8th |year=2008 |isbn=978-0-07-148869-3 |pages= 481–3}}</ref> | |||
* acute ]<ref name=KatzungTrevor2008/> | |||
* ] (in addition to ])<ref name=KatzungTrevor2008/> | |||
* ] poisoning (for which it was developed as an antidote) | |||
|- | |||
| ] (DMSA) | |||
| | |||
*]<ref name=KatzungTrevor2008/> | |||
* ]<ref name=KatzungTrevor2008/> | |||
* ]<ref name=KatzungTrevor2008/> | |||
|- | |||
| ] (DMPS) | |||
| | |||
* severe acute arsenic poisoning<ref name=KatzungTrevor2008/> | |||
* severe acute mercury poisoning<ref name=KatzungTrevor2008/> | |||
|- | |||
| ] | |||
| ''Mainly in:'' | |||
* ]<ref name=KatzungTrevor2008/> | |||
''Occasionally adjunctive therapy in:'' | |||
*]<ref name=KatzungTrevor2008/> | |||
*]<ref name=KatzungTrevor2008/> | |||
*]<ref name=KatzungTrevor2008/> | |||
*]<ref name=KatzungTrevor2008/> | |||
|- | |||
| ] (CaNa<sub>2</sub>-EDTA) | |||
| | |||
*]<ref name=KatzungTrevor2008/> | |||
|- | |||
| ], ] and ] | |||
| | |||
*acute ]<ref name=KatzungTrevor2008/> | |||
*]<ref>{{cite book|last1=Crisponi |first1=Guido |last2=Nurchi |first2=Valeria M. |last3=Lachowicz |first3=Joanna|editor1-last=Sigel|editor1-first=Astrid|editor2-last=Freisinger|editor2-first=Eva | |||
|editor3-last=Sigel|editor3-first=Roland K. O. |editor4-last=Carver|editor4-first=Peggy L.|title=Essential Metals in Medicine:Therapeutic Use and Toxicity of Metal Ions in the Clinic |journal=Metal Ions in Life Sciences |volume=19 |date=2019 |publisher=de Gruyter GmbH|location=Berlin|isbn=978-3-11-052691-2|doi=10.1515/9783110527872-009|pmid=30855104|pages=49–86|chapter=Chapter 3. Iron Chelation for Iron Overload in Thalassemia|s2cid=73727755 }}</ref> | |||
|} | |||
EDTA chelation is approved by the U.S. ] (FDA) for treating lead poisoning and heavy metal toxicity.<ref name=NCCAMQA/> | |||
== |
==Side effects== | ||
{{Multiple issues|section=yes| | |||
{{Unreferencedsection|date=February 2008}} | |||
{{update section|date=June 2024}} | |||
], an orally administered chelator, binding ]. Deferasirox is used in the treatment of ] in people with ].]] | |||
{{expand section|small=no|date=June 2024}} | |||
Chelation therapy is used as a treatment for acute mercury, iron (including in cases of ]), arsenic, lead, ], ] and other forms of ] poisoning. The chelating agent may be administered ], ], or orally, depending on the agent and the type of poisoning. | |||
}} | |||
When used properly in response to a diagnosis of harm from ], side effects of chelation therapy include dehydration, ], ], increased enzymes as would be detected in ], ], and lowered levels of ].<ref name="toxicfive-4">{{Citation |author1 = American College of Medical Toxicology |author1-link = American College of Medical Toxicology |author2 = American Academy of Clinical Toxicology |author2-link = American Academy of Clinical Toxicology |date = February 2013 |title = Five Things Physicians and Patients Should Question |publisher = American College of Medical Toxicology and American Academy of Clinical Toxicology |work = ]: an initiative of the ] |url = http://www.choosingwisely.org/doctor-patient-lists/american-college-of-medical-toxicology-and-the-american-academy-of-clinical-toxicology/ |access-date = 5 December 2013}}, which cites | |||
*{{cite journal|last1=Kosnett|first1=M J|title=Chelation for Heavy Metals (Arsenic, Lead, and Mercury): Protective or Perilous?|journal=Clinical Pharmacology & Therapeutics|volume=88|issue=3|year=2010|pages=412–415|issn=0009-9236|doi=10.1038/clpt.2010.132|pmid=20664538|s2cid=28321495}} | |||
*{{cite journal|author1=Medical Letter consultants|title=Nonstandard uses of chelation therapy.|journal=The Medical Letter on Drugs and Therapeutics|date=September 20, 2010|issue=1347|pages=75–6|pmid=20847718|url=http://secure.medicalletter.org/w1347c|volume=52}} | |||
*{{cite web |url= https://www.fda.gov/ForConsumers/ConsumerUpdates/ucm229358.htm |title=Consumer Updates - FDA Warns Marketers of Unapproved 'Chelation' Drugs |author=Food and Drug Administration |author-link=Food and Drug Administration |work=fda.gov |date=14 October 2010 |access-date=3 July 2014}}</ref> When administered inappropriately, there are the additional risks of ] (low calcium levels), ], and death.<ref name="toxicfive-4"/> | |||
== History == | |||
One example of successful chelation therapy is the case of ], a nuclear worker who became badly contaminated with ] in 1976. He was treated with diethylene triamine pentaacetic acid (DTPA) over many years, removing 41 ] (1.1 ]) of americium from his body. His death, 11 years later, was from unrelated causes. | |||
Chelation therapy can be traced back to the early 1930s, when ], a German chemist working for ], first synthesized ] (EDTA).<ref name=royalsociety>{{cite web|url=http://www.rsc.org/chemistryworld/podcast/CIIEcompounds/transcripts/EDTA.asp|title=Chemistry in its element: compounds|publisher=Royal Society of Chemistry|access-date=30 June 2014}}</ref> Munz was looking for a replacement for ] as a ].<ref name=royalsociety/> Chelation therapy itself began during ] when chemists at the ] searched for an antidote for ], an ]-based ].<ref name=royalsociety/> The chemists learned that EDTA was particularly effective in treating lead poisoning.<ref name=royalsociety/> | |||
Several chelating agents are available, having different affinities for different metals. Common chelating agents include: | |||
Following World War II, chelation therapy was used to treat workers who had painted United States naval vessels with ].<ref name=royalsociety/> In the 1950s, Norman Clarke Sr. was treating workers at a battery factory for lead poisoning when he noticed that some of his patients had improved ] following chelation therapy.<ref>{{cite journal | last1=Grebe | first1=Heidi Braun | last2=Gregory | first2=Philip J. | title=Inhibition of Warfarin Anticoagulation Associated with Chelation Therapy | journal=Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy | publisher=Wiley | volume=22 | issue=8 | year=2002 | issn=0277-0008 | doi=10.1592/phco.22.12.1067.33602 | pages=1067–1069| pmid=12173793 }}</ref> Clarke subsequently administered chelation therapy to patients with angina pectoris and other occlusive vascular disease and published his findings in '']'' in December 1956.<ref name=olszewer88>{{cite journal|title=EDTA Chelation Therapy in Chronic Degenerative Disease|author1=Efrain Olszewer|author2=James P. Carter|journal=Medical Hypotheses|volume=27|pages=41–49|year=1988|issue=1|doi=10.1016/0306-9877(88)90082-5|pmid=3144646}}</ref> He hypothesized that "EDTA could dissolve disease-causing plaques in the coronary systems of human beings."<ref>{{cite journal|title=Chelation therapy for cardiovascular disease. Review and commentary.|journal=Tex Heart Inst J|year=1997|volume=24|issue=2|pages=81–89|author=M R Lewin|pmid=9205980|pmc=325409}}</ref> In a series of 283 patients treated by Clarke et al. From 1956 to 1960, 87% showed improvement in their symptomatology.<ref name=olszewer88/> Other early medical investigators made similar observations of EDTA's role in the treatment of cardiovascular disease (Bechtel, 1956; Bessman, 1957; Perry, 1961; Szekely, 1963; Wenig, 1958: and Wilder, 1962). | |||
* ] (ALA) | |||
* ] (BAPTA) | |||
* ] | |||
* ] | |||
* ] | |||
* ] (DTPA) | |||
* ] (BAL) | |||
* ] (DMPS) | |||
* ] (DMSA) | |||
* ] (CaNa<sub>2</sub>-EDTA) | |||
* ] | |||
* ] | |||
In 1973, a group of practicing physicians created the Academy of Medical Preventics (now the American College for Advancement in Medicine).<ref name=olszewer88/> The academy trains and certifies physicians in the safe administration of chelation therapy.<ref>{{cite web|url=http://issuu.com/clinicaladvisor/docs/february_2014_issue/25|title=The facts and fictions of chelation therapy|author=Ronald L. Hoffman|publisher=The Clinical Advisor|date=February 2014|access-date=30 June 2014}}</ref> Members of the academy continued to use EDTA therapy for the treatment of vascular disease and developed safer administration protocols.<ref name=olszewer88/> | |||
== Use in alternative medicine == | |||
In the 1960s, BAL was modified into ], a related ] with far fewer side effects.<ref name=Kalia2005>{{cite journal |last1=Kalia |first1=Kiran |last2= Flora |first2= Swaran J.S. |title=Strategies for safe and effective therapeutic measures for chronic arsenic and lead poisoning |journal=Journal of Occupational Health |publisher= Japan Society for Occupational Health |volume=47 |issue=1 |pages=1–21 |year= 2005 |pmid=15703449 |doi= 10.1539/joh.47.1|url=https://www.jstage.jst.go.jp/article/joh/47/1/47_1_1/_pdf|doi-access=free }}</ref> DMSA quickly replaced both BAL and EDTA as the primary treatment for lead, arsenic and mercury poisoning in the United States. Esters of DMSA have been developed which are reportedly more effective; for example, the monoisoamyl ester (MiADMSA) is reportedly more effective than DMSA at clearing mercury and cadmium.<ref name=Kalia2005/> Research in the former Soviet Union led to the introduction of ], another dithiol, as a mercury-chelating agent. The Soviets also introduced ], which is transformed by the body into the dithiol ], a mercury- and arsenic-chelating agent. DMPS has experimental status in the United States, while ALA is a common nutritional supplement. | |||
] uses chelation therapy in the treatment of heart disease.<ref>{{cite journal |author=Ernst E |title=Chelation therapy for coronary heart disease: An overview of all clinical investigations |journal=Am. Heart J. |volume=140 |issue=1 |pages=139–41 |year=2000 |pmid=10874275 |doi=10.1067/mhj.2000.107548}}</ref> Currently there is a US National Insitutes of Health trial (TACT) being conducted on the chelation therapy's efficacy in treating heart disease.<ref name=TACT>NCCAMN.</ref> The proposed study has been criticized as unnecessary and possibly dangerous.<ref name=Kimball2008></ref> | |||
Since the 1970s, iron chelation therapy has been used as an alternative to regular ] to treat excess iron stores in people with ].<ref name='CDC_Hemo'>{{citation|chapter-url=https://www.cdc.gov/ncbddd/hemochromatosis/training/treatment/monitoring_treatment.htm |title=Hemochromatosis for healthcare professionals |chapter= Treatment & Management: Monitoring Treatment |access-date=29 March 2008 |date= 1 November 2007 |publisher= Division of Nutrition and Physical Activity, National Center for Chronic Disease Prevention and Health Promotion, ], ] |archive-url = https://web.archive.org/web/20080224192906/http://www.cdc.gov/ncbddd/hemochromatosis/training/treatment/monitoring_treatment.htm <!-- Bot retrieved archive --> |archive-date = 2008-02-24}}</ref> Other chelating agents have been discovered. They all function by making several chemical bonds with metal ions, thus rendering them much less chemically reactive. The resulting complex is water-soluble, allowing it to enter the bloodstream and be excreted harmlessly. | |||
=== Cilantro === | |||
] (coriander) has been tested in mice,<ref>{{cite journal |author=Aga M, Iwaki K, Ueda Y, ''et al'' |title=Preventive effect of Coriandrum sativum (Chinese parsley) on localized lead deposition in ICR mice |journal=Journal of ethnopharmacology |volume=77 |issue=2-3 |pages=203–8 |year=2001 |pmid=11535365 |doi= |doi=10.1016/S0378-8741(01)00299-9}}</ref> and is present in numerous alternative medications. Although cilantro was widely described as a chelator of lead, mercury, or other heavy metals in internet literature,<ref>{{cite journal |author=Omura Y, Beckman SL |title=Role of mercury (Hg) in resistant infections & effective treatment of Chlamydia trachomatis and Herpes family viral infections (and potential treatment for cancer) by removing localized Hg deposits with Chinese parsley and delivering effective antibiotics using various drug uptake enhancement methods |journal=Acupuncture & electro-therapeutics research |volume=20 |issue=3-4 |pages=195–229 |year=1995 |pmid=8686573 |doi=}}</ref><ref>{{cite journal |author=Omura Y, Shimotsuura Y, Fukuoka A, Fukuoka H, Nomoto T |title=Significant mercury deposits in internal organs following the removal of dental amalgam, & development of pre-cancer on the gingiva and the sides of the tongue and their represented organs as a result of inadvertent exposure to strong curing light (used to solidify synthetic dental filling material) & effective treatment: a clinical case report, along with organ representation areas for each tooth |journal=Acupuncture & electro-therapeutics research |volume=21 |issue=2 |pages=133–60 |year=1996 |pmid=8914687 |doi=}}</ref> and is often used as such, there is little research about such claims.<ref>{{cite journal|url=http://medherb.com/eletter/Cilantro-Millet.pdf|format=PDF|author= Millet, John|title=Cilantro, Chlorella and Heavy Metals|journal=Medical Herbalism|volume=14|issue=4|accessdate=2007-11-11}}</ref> | |||
Calcium-disodium EDTA chelation has been studied by the U.S. ] for treating ].<ref name=NCCAMQA>{{cite web | url=http://nccam.nih.gov/news/2002/chelation/q-and-a.htm|publisher=] (NCCAM), ], ] | title=Questions and Answers: The NIH Trial of EDTA Chelation Therapy for Coronary Artery Disease |issue= NCCAM Pub. No. D166 |date= March 2007 | access-date=11 November 2007 |archive-url = https://web.archive.org/web/20071015044954/http://nccam.nih.gov/news/2002/chelation/q-and-a.htm <!-- Bot retrieved archive --> |archive-date = 2007-10-15}}</ref> In 1998, the U.S. ] (FTC) pursued the American College for Advancement in Medicine (ACAM), an organization that promotes "complementary, alternative and integrative medicine" over the claims made regarding the treatment of ] in advertisements for EDTA chelation therapy. The FTC concluded that there was a lack of scientific studies to support these claims and that the statements by the ACAM were false.<ref name= "FTC ACAM timeline">{{cite web | url = http://www.ftc.gov/os/1999/07/9623147c3881acamcmp.htm | title = American College for Advancement in Medicine: Case Timeline |volume= FTC Matter/File Number: 962 3147 |issue= Docket Number:C–3882 | publisher = ] (FTC) | date = 13 July 1999 | access-date = 1 July 2010 |type= FTC Case Timeline with links to documents }}</ref> In 1999, the ACAM agreed to stop presenting chelation therapy as effective in treating heart disease, avoiding legal proceedings.<ref>{{cite web | url = http://www.ftc.gov/sites/default/files/documents/cases/1998/12/9623147agr.htm | title = United States of America Federal Trade Commission In the Matter of American College for Advancement in Medicine, a corporation. File no. 962 3147. '''Agreement Containing Consent Order''' | publisher = ] | date = 12 January 1998 | access-date = 1 July 2010}} {{cite web |url= http://www.ftc.gov/sites/default/files/documents/cases/1998/12/9623147att.htm |title= Attachment A |type= Notification letter}}</ref> In 2010 the U.S. Food and Drug Administration (FDA) warned companies who sold over-the-counter (OTC) chelation products and stated that such "products are unapproved drugs and devices and that it is a violation of federal law to make unproven claims about these products. There are no FDA-approved OTC chelation products."<ref name=FDA_2010_warning/> | |||
=== Heart disease === | |||
==Controversies== | |||
Some alternative practitioners use chelation to treat ]. The use of EDTA chelation therapy as a treatment for coronary artery disease is currently being studied by the ], but no claims or findings are expected before 2009.<ref>{{cite web| url=http://www.clinicaltrials.gov/ct/show/NCT00044213?order=1 | title=Trial to Assess Chelation Therapy (TACT) | publisher=U.S. National Institutes of Health | accessdate=2007-11-11}}</ref><ref name=NCCAMQA>{{cite web | url=http://nccam.nih.gov/news/2002/chelation/q-and-a.htm|publisher=National Center for Complementary and Alternative Medicine (NCCAM) | title=Questions and Answers: The NIH Trial of EDTA Chelation Therapy for Coronary Artery Disease | accessdate=2007-11-11}}</ref> Chelation therapy is not approved by the ] to treat coronary artery disease.<ref name="AHA">{{cite web |url=http://www.americanheart.org/presenter.jhtml?identifier=4493 |title=American Heart Association: Chelation Therapy |accessdate=2008-04-03}}</ref> | |||
{{Update section|reason=Almost all of the sources cited were published more than 10 years ago. ] prefers sources within the last 5 years or so|date=May 2024}} | |||
{{More medical citations needed|date=May 2024}} | |||
{{POV section|date=May 2024}} | |||
In 1998, the U.S. ] (FTC) charged that the web site of the American College for Advancement in Medicine (ACAM) and a brochure they published had made false or unsubstantiated claims. In December 1998, the FTC announced that it had secured a consent agreement barring ACAM from making unsubstantiated advertising claims that chelation therapy is effective against atherosclerosis or any other disease of the circulatory system.<ref name= "FTC ACAM timeline"/><ref>{{cite press release |url= http://www.ftc.gov/news-events/press-releases/1998/12/medical-association-settles-false-advertising-charges-over |date=8 December 1998 |title= Medical Association Settles False Advertising Charges Over Promotion of 'Chelation Therapy' |author= Federal Trade Commission |access-date= 17 January 2014|author-link=Federal Trade Commission }}</ref> | |||
In August 2005, doctor error led to the death of a five-year-old boy with ] who was undergoing chelation therapy.<ref name=Atwood2008/> Others, including a three-year-old non-autistic girl and a non-autistic adult, have died while undergoing chelation therapy.<ref name=Atwood2008/> These deaths were due to cardiac arrest caused by ] during chelation therapy. In two of the cases, hypocalcemia appears to have been caused by the administration of Na2EDTA (]) and in the third case the type of EDTA was unknown.<ref>{{cite journal |journal= ] |year= 2006 |volume= 118 |issue= 2 |pages= e534–6 |title= Deaths resulting from hypocalcemia after administration of edetate disodium: 2003–2005 |last1= Brown |first1= M.J. |last2= Willis |first2= T. |last3= Omalu |first3= B. |last4= Leiker |first4= R. |doi= 10.1542/peds.2006-0858 |pmid= 16882789 |s2cid= 28656831 |url= http://pediatrics.aappublications.org/cgi/content/full/118/2/e534 |access-date= 2007-11-13 |archive-date= 2009-07-27 |archive-url= https://web.archive.org/web/20090727080307/http://pediatrics.aappublications.org/cgi/content/full/118/2/e534 }}</ref><ref>{{cite journal |last1= Baxter |first1= A.J. |last2= Krenzelok |first2= E.P. |title= Pediatric fatality secondary to EDTA chelation |journal= ] |volume= 46|issue= 10|pages= 1083–4|year=2008 |pmid=18949650 |doi=10.1080/15563650701261488|s2cid= 24576683 }}</ref> Only the three-year-old girl had been found to have an elevated ] and resulting low iron levels and anemia, which is the conventional medical cause for administration of chelation therapy.<ref>{{cite journal |url= https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5508a3.htm |title= Deaths associated with hypocalcemia from chelation therapy - Texas, Pennsylvania, and Oregon, 2003-2005 |journal= ] |year= 2006 |volume= 55 |issue= 8 |pages= 204–7 |publisher= ]|pmid= 16511441 |author1= Centers for Disease Control Prevention (CDC) }}</ref> | |||
The ] contends that there is currently "no scientific evidence to demonstrate any benefit from this form of therapy" and that the "United States Food and Drug Administration (FDA), the National Institutes of Health (NIH) and the American College of Cardiology all agree with the American Heart Association" that "there have been no adequate, controlled, published scientific studies using currently approved scientific methodology to support this therapy for cardiovascular disease."<ref name="AHA"/> | |||
According to protocol,<ref>{{Cite journal|last=Drugs|first=Committee on|date=1995-07-01|title=Treatment Guidelines for Lead Exposure in Children|url=https://pediatrics.aappublications.org/content/96/1/155|journal=Pediatrics|language=en|volume=96|issue=1|pages=155–159|doi=10.1542/peds.96.1.155 |issn=0031-4005|pmid=7596706|s2cid=2477907 }}</ref> EDTA should not be used in the treatment of children.<ref>{{cite book |last= Van der Schaar |first= Peter J. |title= Textbook of Clinical Metal Toxicology |publisher= International Board of Clinical Metal Toxicology |location= Leende, Netherlands |year= 2011 |edition= 10th }}{{Unreliable medical source|date=January 2014}}{{Full citation needed|date=January 2014}}</ref> More than 30 deaths have been recorded in association with IV-administered disodium EDTA since the 1970s.<ref name=Atwood2008/> | |||
=== Autism === | |||
===Use in alternative medicine=== | |||
Based on the speculation that ] may trigger the symptoms of autism, some parents have turned to alternative medicine practitioners who provide chelation therapy. However, the only evidence to support this belief is ]. There is strong ] evidence that refutes links between environmental triggers, in particular ]-containing ]s and the onset of autistic symptoms. No scientific data supports the claim that the mercury in the vaccine preservative ] causes autism<ref>{{cite journal |journal= Can J Neurol Sci |date=2006 |volume=33 |issue=4 |pages=341–6 |title= Immunizations and autism: a review of the literature |author= Doja A, Roberts W |pmid=17168158}}</ref> or its symptoms,<ref>{{cite journal |journal= N Engl J Med |volume=357 |issue=13 |pages=1281–92 |year=2007 |title= Early thimerosal exposure and neuropsychological outcomes at 7 to 10 years |author= Thompson WW, Price C, Goodson B ''et al.'' |pmid=17898097 |url=http://content.nejm.org/cgi/content/full/357/13/1281 |doi= 10.1056/NEJMoa071434}}</ref> and there is no scientific support for chelation therapy as a treatment for autism.<ref>{{cite journal |journal= Pediatr Clin North Am |date=2007 |volume=54 |issue=6 |pages=983–1006 |title= Complementary and alternative medical therapies for attention-deficit/hyperactivity disorder and autism |author= Weber W, Newmark S |doi=10.1016/j.pcl.2007.09.006 |pmid=18061787}}</ref><ref name='NYT_autism'>{{cite news | first=Sandra | last=Blakeslee | title=Panel Finds No Evidence To Tie Autism To Vaccines | date=2004-05-19 | url =http://query.nytimes.com/gst/fullpage.html?res=9C02E2D6123FF93AA25756C0A9629C8B63 | work =New York Times | pages = | accessdate = 2008-02-01 }} "An examination of scientific studies worldwide has found no convincing evidence that vaccines cause autism, according to a committee of experts appointed by the Institute of Medicine." </ref> | |||
In ], some practitioners claim chelation therapy can treat a variety of ailments, including ] and ].<ref>{{cite journal |last=Ernst |first= E. |author-link= Edzard Ernst |title=Chelation therapy for coronary heart disease: An overview of all clinical investigations |journal=American Heart Journal |volume=140 |issue=1 |pages=139–41 |year=2000 |pmid=10874275 |doi=10.1067/mhj.2000.107548}}</ref><ref name=Weber/> The use of chelation therapy by alternative medicine practitioners for behavioral and other disorders is considered ]; there is no proof that it is effective.<ref>{{cite web |url= http://www.baam.emich.edu/baamnewsarchive/BAAMbnachelationdeath.htm |title= Boy with autism dies during 'chelation therapy' |work= Behavior News |publisher= Behavior Analysis Association of Michigan |date= 30 August 2005 |access-date= 4 August 2010 |archive-url= https://web.archive.org/web/20161129083241/http://www.baam.emich.edu/baamnewsarchive/BAAMbnachelationdeath.htm |archive-date= 29 November 2016 }}</ref> Chelation therapy prior to heavy metal testing can artificially raise urinary heavy metal concentrations ("provoked" urine testing) and lead to inappropriate and unnecessary treatment.<ref name="toxicfive">{{Citation |author1 = American College of Medical Toxicology |author1-link = American College of Medical Toxicology |author2 = American Academy of Clinical Toxicology |author2-link = American Academy of Clinical Toxicology |date = February 2013 |title = Five Things Physicians and Patients Should Question |publisher = American College of Medical Toxicology and American Academy of Clinical Toxicology |work = ]: an initiative of the ] |url = http://www.choosingwisely.org/doctor-patient-lists/american-college-of-medical-toxicology-and-the-american-academy-of-clinical-toxicology/ |access-date = 5 December 2013}}</ref> The ] and the ] warn the public that chelating drugs used in chelation therapy may have serious side effects, including liver and kidney damage, ] changes, ] and in some cases even death of the patient.<ref name="toxicfive"/> | |||
====Cancer==== | |||
The hypothesis of ] as a cause for autism was proposed by Bernard, Enayati, Roger, Binstock, and Redwood in 2002<ref>Bernard, S., Enayati, A., Roger, T., Binstock, T., & Redwood, L. (2002). The role of mercury in the pathogenesis of autism. Molecular Psychiatry, 7, S42-S43.</ref>. These authors stated that symptoms of autism arise from exposure to mercury. They further state that symptoms of autism tend to emerge when children are administered vaccines, the rise in children with autism in the 1990’s coincided with the introduction of two mercury-containing immunizations, and finally, patients with autism have been found to have levels of mercury in their systems<ref>Bernard, S., Enayati, A., Roger, T., Binstock, T., & Redwood, L. (2002). The role of mercury in the pathogenesis of autism. Molecular Psychiatry , 7, S42-S43.</ref>. An important problem with this theory is the fact that the symptoms of autism do not perfectly resemble symptoms of mercury poisoning. Though mercury poisoning can cause impaired social interactions, communication problems, and stereotypic behaviors<ref>Bernard, S., Enayati, A., Roger, T., Binstock, T., & Redwood, L. (2002). The role of mercury in the pathogenesis of autism. Molecular Psychiatry , 7, S42-S43.</ref>, as seen in autism, it also causes “ataxia, constricted visual fields, peripheral neuropathy, hypertension, skin eruption, and thrombocytopenia”<ref>Ng, D. K.-K., Chan, C.-H., Soo, M.-T., & Lee, R. S.-Y. (2007). Low-level chronic mercury exposure in children and adolescents: meta-analysis. Pediatrics International , 49, 80-87.</ref> - symptoms not seen in children with autism. Thimerosal, the mercury-containing preservative found in vaccines, has been removed from nearly all childhood immunizations. In one state study, however, the Caifornia Department of Developmental Services found that the prevalence of autism increased from January 1995 to March 2007, concluding that exposure to thimerosal does not lead to autism<ref>Schechter, R., & Grether, J. K. (2008). Continuing increases in autism reported to California's developmental services system. Archives of General Psychiatry , 65 (1), 19-24.</ref>. Nevertheless, caregivers of children with autism have sought out treatment to rid mercury and other heavy metals from the body, in a process known as chelation. | |||
The ] says of chelation therapy: "Available scientific evidence does not support claims that it is effective for treating other conditions such as cancer. Chelation therapy can be toxic and has the potential to cause kidney damage, ], and even death."<ref name=acs/> | |||
====Cardiovascular disease==== | |||
Chelation therapy was used by the British after World War II to remove arsenic, lead, and other metals created by the during the war due to lack of materials. Patients’ conditions improved as these metals were removed from their bodies<ref>Nash, R. A. (2005). Metals in medicine. Alternative Therapies in Health and Medicine , 11 (4), 18-25.</ref>. Today, chelation therapy is used to rid the body of toxic metals such as lead and mercury. Doctors should take a blood test to assess current kidney and liver function, nutrient status, and blood-lipid levels before chelation therapy begins<ref>Klotter, J. (2006). Chelation for autism. Townsend Letter: The Examiner of Alternative Medicine , 30, p. 273.</ref>. A gluten-free, casein-free (GFCF) diet and supplemental changes, including shots of vitamin B12, may be used. Treatment may be applied to the skin via a transdermal patch<ref>Bridges, S. (2006). The promise of chelation. Mothering , 54-61.</ref>. Another treatment is administered intravenously, a process that takes 2-3 hours, costs about $100 per treatment, and 20-30 treatments are often required<ref>Klotter, J. (2006). Chelation for autism. Townsend Letter: The Examiner of Alternative Medicine , 30, p. 273.</ref>. | |||
According to the findings of a 1997 ], ] chelation therapy is not effective as a treatment for ] and this use is not approved in the United States by the ] (FDA).<ref name="Ernst1997">{{cite journal |url=http://circ.ahajournals.org/content/96/3/1031.full |journal= ] |title= Chelation therapy for peripheral arterial occlusive disease: A systematic review |last= Ernst |first= Edzard |author-link= Edzard Ernst |volume= 96 |issue= 3 |pages= 1031–3 |pmid= 9264515 |doi= 10.1161/01.CIR.96.3.1031 |year= 1997}}</ref> | |||
The ] stated in 1997 that there is "no scientific evidence to demonstrate any benefit from this form of therapy." The FDA, the ] (NIH) and the ] "all agree with the American Heart Association" that "there have been no adequate, controlled, published scientific studies using currently approved scientific methodology to support this therapy for cardiovascular disease."<ref name="Ernst1997"/> {{citation needed span|They speculate{{speculation inline|date=May 2024}} that any improvement among heart patients undergoing chelation therapy can be attributed to the placebo effect and generally recommended lifestyle changes such as "quitting smoking, losing weight, eating more fruits and vegetables, avoiding foods high in saturated fats and exercising regularly." They also are concerned that patients could put off proven treatments for heart disease like drugs or surgery.|date=May 2024}}{{dubious|date=May 2024}} | |||
Some common chelating agents are ] (ethylenediaminetetraacetic acid), ] (sodium 2,3 dimercaptopropane-1 sulfate), ] (thiamine tetrahydrofurfuryl disulfide), and DMPS (2,3 dimercaptosuccinic acid). EDTA and DMSA are only approved for the removal of lead by the Food and Drug Administration while DMPS and TTFD are not approved by the FDA. These drugs bind to heavy metals in the body and prevent them from binding to other agents. They are then excreted from the body. The chelating process also removes vital nutrients such as vitamins C and E, therefore these must be supplemented<ref>Bridges, S. (2006). The promise of chelation. Mothering , 54-61.</ref>. | |||
A systematic review published in 2005 found that controlled scientific studies did not support chelation therapy for heart disease.<ref>{{cite journal |last1=Seely |first1= D.M. |last2= Wu |first2= P. |last3= Mills |first3= E.J. |title=EDTA chelation therapy for cardiovascular disease: A systematic review |journal=] |volume=5|page=32 |year=2005 |pmid=16262904 |pmc=1282574 |doi=10.1186/1471-2261-5-32 |doi-access= free }}</ref> It found that very small trials and uncontrolled descriptive studies have reported benefits while larger controlled studies have found results no better than ]. | |||
Some parents of children with autism have reported significant gains in their children’s symptoms following chelation therapy. They contend that within weeks of the initial treatment, their children have made drastic improvements in behavior and social engagement. Younger children have reportedly made faster and more significant results<ref>Bridges, S. (2006). The promise of chelation. Mothering , 54-61.</ref>. However, other parents have stated that chelation therapies made no difference in their children’s developmental outcomes<ref>Laidler, J. R. (n.d.). Through the looking glass: my involvment with autism quackery. Retrieved May 26, 2008, from Autism Watch: http://www.autism-watch.org/about/bio2.shtml</ref>. | |||
In 2009, the Montana Board of Medical Examiners issued a position paper concluding that "chelation therapy has no proven efficacy in the treatment of cardiovascular disease, and in some patients could be injurious."<ref name=MontanaBME>{{cite web |url= http://bsd.dli.mt.gov/license/bsd_boards/med_board/pdf/edtachelation.pdf |title= EDTA Chelation for Cardiovascular Disease |author= Montana Board of Medical Examiners (BME) |type= BME Position Paper |publisher= Business Standard Div., Montana Dept. of Labor and Industry |date= 14 May 2009 |archive-url= https://web.archive.org/web/20100204121215/http://bsd.dli.mt.gov/license/bsd_boards/med_board/pdf/edtachelation.pdf |archive-date= 2010-02-04}}</ref> | |||
There are significant risks associated with the use of chelation for the treatments of autism. The deaths of two children were reported due to hypocalemia and cardiac arrest after receiving chelation therapy<ref>Schechtman, M. A. (2007). Scientifically unsupported therapies in the treatment of young children with autism spectrum disorders. Psychiatric Annals , 37 (9), 639-645.</ref>. Long-term use of the chelating agent SMSA can cause liver damage, zinc deficiency, and bone marrow suppression<ref>Klotter, J. (2006). Chelation for autism. Townsend Letter: The Examiner of Alternative Medicine , 30, p. 273.</ref>. Mineral deficiencies, cardiovascular effects (blood pressure drop), kidney problems, and the possibility of distributing mercury throughout the body may also occur. However, using a combination of chelators, supplements, diet changes, and regular lab tests can reportedly reduce the risk of side effects<ref>Bridges, S. (2006). The promise of chelation. Mothering , 54-61.</ref>. | |||
The U.S. ] (NCCAM) conducted a trial on the chelation therapy's safety and efficacy for patients with coronary artery disease.<ref name="TACT">{{cite journal|url=http://www.clinicaltrials.gov/ct2/show/NCT00044213|title=Trial to Assess Chelation Therapy (TACT)|date=August 2013|journal=]|publisher=], ], ]|issue=ClinicalTrials.gov identifier NCT00044213|last1=Md|first1=Gervasio Lamas}}</ref> NCCAM Director ] cited the "widespread use of chelation therapy in lieu of established therapies, the lack of adequate prior research to verify its safety and effectiveness, and the overall impact of coronary artery disease" as factors motivating the trial.<ref>{{cite press release|url=http://nccam.nih.gov/news/2002/chelation/pressrelease.htm|title=NIH Launches Large Clinical Trial on EDTA Chelation Therapy for Coronary Artery Disease|work=NIH News|publisher=(NIH)|author1=] (NIH)|author2-link=National Center for Complementary and Alternative Medicine|author2=National Center for Complementary and Alternative Medicine|author3=National Heart, Lung, and Blood Institute|date=7 August 2002|access-date=28 December 2008|archive-url=https://web.archive.org/web/20141228031307/http://nccam.nih.gov/news/2002/chelation/pressrelease.htm|archive-date=28 December 2014}}</ref> The study has been criticized by some who said it was unethical, unnecessary and dangerous, and that multiple studies conducted prior to it demonstrated that the treatment provides no benefit.<ref name="Atwood2008" /> | |||
Because of the lack of empirical support in controlled studies and the possibility of dangerous side effects, chelation therapy for the treatment of autism is not recommended. The most effective known interventions for children with autism are educational and behavioral therapies. | |||
The US ] began the Trial to Assess Chelation Therapy (TACT) in 2003.<ref name="TACT" /> Patient enrollment was to be completed around July 2009<ref name="NCCAMQA" /> with final completion around July 2010,<ref name=TACT/> but enrollment in the trial was voluntarily suspended by organizers in September 2008 after the ] began investigating complaints such as inadequate ].<ref name="washingtonpost">{{cite news|url=https://www.washingtonpost.com/wp-dyn/content/article/2008/09/25/AR2008092503085.html|title=Government probes chelation-heart disease study|date=2008-09-25|newspaper=Washington Post|access-date=2008-09-26|agency=Associated Press|location=Washington, DC}}{{dead link|date=June 2021|bot=medic}}{{cbignore|bot=medic}}</ref> Additionally, the trial was criticized for lacking prior Phase I and II studies, and critics summarized previous controlled trials as having "found no evidence that chelation is superior to placebo for treatment of CAD or PVD."<ref name=Atwood2008/> The same critics argued that methodological flaws and lack of ] made the trial "unethical, dangerous, pointless, and wasteful."<ref name=Atwood2008/> The American College of Cardiology supported the trial and research to explore whether chelation therapy was effective in treating heart disease.<ref name=washingtonpost/> Evidence of ] and other ] convictions among (chelation proponent) investigators further undermined the credibility of the trial.<ref name="NIH-Fraudsters">{{cite web|url=http://www.sciencebasedmedicine.org/nih-awards-30-million-research-dollars-to-convicted-felons-cliffs-notes-version/|title=NIH Awards $30 Million Research Dollars To Convicted Felons: Cliff's Notes Version|author=Jones, Valerie|date=2009-07-09|publisher=]|access-date=December 5, 2014}}</ref> | |||
== Controversy == | |||
The final results of TACT were published in November 2012. The authors concluded that disodium EDTA chelation "modestly" reduced the risk of adverse cardiovascular outcomes among stable patients with a history of ].<ref>{{cite journal|title=Effect of Disodium EDTA Chelation Regimen on Cardiovascular Events in Patients With Previous Myocardial Infarction: The TACT Randomized Trial |author=Gervasio D. Lamas |journal=JAMA|year=2013|volume=309|issue=12|pages=1241–1250|doi=10.1001/jama.2013.2107|pmid=23532240 |pmc=4066975}}</ref> The study also showed a "marked" reduction in cardiovascular events in diabetic patients treated with EDTA chelation.<ref>{{cite journal|title=The Effect of an EDTA-based Chelation Regimen on Patients With Diabetes Mellitus and Prior Myocardial Infarction in the Trial to Assess Chelation Therapy (TACT)|journal=Circulation: Cardiovascular Quality and Outcomes|volume=7|issue=1|pages=15–24|publisher=CircoutComes|doi=10.1161/CIRCOUTCOMES.113.000663|pmid=24254885|pmc=4111470|year=2014|last1=Escolar|first1=E.|last2=Lamas|first2=G. A.|last3=Mark|first3=D. B.|last4=Boineau|first4=R.|last5=Goertz|first5=C.|last6=Rosenberg|first6=Y.|last7=Nahin|first7=R. L.|last8=Ouyang|first8=P.|last9=Rozema|first9=T.|last10=Magaziner|first10=A.|last11=Nahas|first11=R.|last12=Lewis|first12=E. F.|last13=Lindblad|first13=L.|last14=Lee|first14=K. L.}}</ref> An editorial published in the '']'' said that "the study findings may provide novel hypotheses that merit further evaluation to help understand the pathophysiology of secondary prevention of vascular disease."<ref>{{cite journal|author1=Bauchner H|author2=Fontanarosa PB|author3=Golub RM|title=Evaluation of the Trial to Assess Chelation Therapy (TACT): The Scientific Process, Peer Review, and Editorial Scrutiny|journal=JAMA|year=2013|volume=309|issue=12|pages=1291–1292|doi=10.1001/jama.2013.2761|pmid=23532245|doi-access=free}}</ref> Critics of the study characterized the study as showing no support for the use of chelation therapy in coronary heart disease, particularly the claims to reduce the need for ] (CABG, pronounced "cabbage").<ref name="Attwood2012">{{cite web |url= http://www.sciencebasedmedicine.org/index.php/the-trial-to-assess-chelation-therapy-equivocal-as-predicted/ |title= The Trial to Assess Chelation Therapy: Equivocal as Predicted |first= Kimball |last= Atwood |author-link= Kimball Atwood |work= ] |date= 4 November 2012}}</ref><ref name="Gorski2012">{{cite web |url= http://www.sciencebasedmedicine.org/index.php/the-result-of-the-trial-to-assess-chelation-therapy-tact-as-underwhelming-as-expected/ |title= The result of the Trial to Assess Chelation Therapy (TACT): As underwhelming as expected |first= David |last= Gorski |author-link= David Gorski |work= ] |date= 5 November 2012}}</ref><ref>{{cite web | url = http://newsroom.heart.org/pr/aha/chelation-therapy-doesn-t-alter-240495.aspx | title = Chelation therapy doesn't alter quality of life in heart attack patients | date = 4 November 2012 | publisher = ] | access-date = 30 November 2012 | archive-url = https://web.archive.org/web/20121109153039/http://newsroom.heart.org/pr/aha/chelation-therapy-doesn-t-alter-240495.aspx | archive-date = 9 November 2012 | df = dmy-all }}</ref> | |||
The efficacy, safety, and much of the theory behind these alternative practices are disputed by the medical community. In 2001, researchers at the University of Calgary reported that cardiac patients receiving chelation therapy fared no better than those who received ] treatment.<ref>{{cite journal |author=Knudtson ML, Wyse DG, Galbraith PD, ''et al'' |title=Chelation therapy for ischemic heart disease: a randomized controlled trial |journal=JAMA |volume=287 |issue=4 |pages=481–6 |year=2002 |pmid=11798370 |doi= |doi=10.1001/jama.287.4.481}}</ref> | |||
==== Autism ==== | |||
In 2003, the Supreme Court of Missouri, in ''State Board of Registration for the Healing Arts v. McDonagh'', 123 S.W.3d 146, overturned a decision of the State Board of Registration sanctioning a doctor who used chelation therapy for the treatment of heart disease. The Court held that the therapy was not harming patients, and the standard for determining repeated negligence in using an alternative therapy such as chelation is not whether it is popular or commonly accepted by the medical community, but rather whether heart specialists would consider its use to be reasonable. | |||
{{Main|Thiomersal controversy}} | |||
] says that ] is one of the conditions for which chelation therapy has been falsely promoted as effective, and practitioners falsify diagnoses of metal poisoning to trick parents into having their children undergo the risky process.<ref name="qw">{{cite web|url=http://www.quackwatch.org/01QuackeryRelatedTopics/chelationindex.html|title=Why Chelation Therapy Should Be Avoided|date=15 May 2004|publisher=]|access-date=7 October 2013}}</ref> {{as of|2008}}, up to 7% of children with autism worldwide<ref name="Davis-review" /> had been subjected to chelation therapy.<ref name=stokstad>{{cite journal |journal=Science |year=2008 |volume=321 |issue=5887 |page=326 |title= Stalled trial for autism highlights dilemma of alternative treatments |last= Stokstad |first= E. |doi=10.1126/science.321.5887.326 |pmid=18635766|s2cid=206581219 |doi-access=free }}</ref> The death of two children in 2005 was caused by the administration of chelation treatments, according to the American ]. One of them had autism.<ref>{{Cite news|url=http://www.nbcnews.com/id/11640868/ns/health-childrens_health/t/fda-links-child-deaths-chelation-therapy/|title=FDA links child deaths to chelation therapy|date=February 3, 2006|work=NBC News / Associated Press|access-date=August 30, 2018|archive-url=https://web.archive.org/web/20180830103211/http://www.nbcnews.com/id/11640868/ns/health-childrens_health/t/fda-links-child-deaths-chelation-therapy/|archive-date=August 30, 2018}}</ref> Parents either have a doctor use a treatment for lead poisoning, or buy unregulated supplements, in particular ] and ].<ref name=stokstad/> ], an ], considers this use of chelation therapy unethical and potentially dangerous.<ref name='AspFF'>{{cite web|url=http://www.aspiesforfreedom.com/ |title=Aspies For Freedom |access-date=24 February 2009 |publisher=] |archive-url= https://web.archive.org/web/20100117120908/http://aspiesforfreedom.com/ |archive-date= 2010-01-17}}</ref> There is little to no credible scientific research that supports the use of chelation therapy for the effective treatment of autism.<ref name=Weber>{{cite journal |journal= ] |year=2007 |volume=54 |issue=6 |pages=983–1006 |title= Complementary and alternative medical therapies for attention-deficit/hyperactivity disorder and autism |last1= Weber |first1= W. |last2= Newmark |first2= S. |doi=10.1016/j.pcl.2007.09.006 |pmid=18061787}}</ref><ref name="Davis-review">{{cite journal | display-authors=4 | first1=Tonya N. | first10=Austin | last1=Davis | last10=Mulloy | title=Chelation treatment for autism spectrum disorders: A systematic review | last2=O'Reilly | first2=Mark | last3=Kang | first3=Soyeon | last4=Lang | first4=Russell | last5=Rispoli | first5=Mandy | last6=Sigafoos | first6=Jeff | last7=Lancioni | first7=Giulio | last8=Copeland | first8=Daelynn | last9=Attai | first9=Shanna | journal=] | year=2013 | volume=7 | issue=1 | pages=49–55 | doi=10.1016/j.rasd.2012.06.005 | quote=However, given the significant methodological limitations of these studies, the research reviewed here does not support the use of chelation as a treatment for ASD}}</ref><ref name="NYT_autism">{{cite news | url=https://query.nytimes.com/gst/fullpage.html?res=9C02E2D6123FF93AA25756C0A9629C8B63 | title=Panel finds no evidence to tie autism to vaccines | date=19 May 2004 | access-date=2008-02-01 | last=Blakeslee | first=Sandra | newspaper=]}}</ref><ref>{{cite journal|pmc=3566884|year=2012|last1=Blaucok-Busch|first1=E.|last2=Amin|first2=O.R.|last3=Dessoki|first3=H.H.|last4=Rabah|first4=T.|title=Efficacy of DMSA therapy in a sample of Arab children with autistic spectrum disorder|volume=7|issue=3|pages=214–21|journal=Mædica|pmid=23400264}}</ref><ref>{{cite journal|pmc=2770991|last1=Adams|first1=J.B.|last2=Baral|first2=M.|last3=Geis|first3=E.|last4=Mitchell|first4=J.|last5=Ingram|first5=J.|last6=Hensley|first6=A.|last7=Zappia|first7=I.|last8=Newmark|first8=S.|last9=Gehn|first9=E.|last10=Rubin|first10=R.A.|last11=Mitchell|first11=K.|last12=Bradstreet|first12=J.|last13=El-Dahr|first13=J.|display-authors= 4 |title=Safety and efficacy of oral DMSA therapy for children with autism spectrum disorders: Part B - Behavioral results|volume=9|page=17|doi=10.1186/1472-6904-9-17|journal=BMC Clinical Pharmacology|year=2009|pmid=19852790 |doi-access=free }}</ref><ref>{{cite journal|pmc=2809421|year=2009|last1=Adams|first1=J.B.|last2=Baral|first2=M.|last3=Geis|first3=E.|last4=Mitchell|first4=J.|last5=Ingram|first5=J.|last6=Hensley|first6=A.|last7=Zappia|first7=I.|last8=Newmark|first8=S.|last9=Gehn|first9=E.|last10=Rubin|first10=R.A.|last11=Mitchell|first11=K.|last12=Bradstreet|first12=J.|last13=El-Dahr|first13=J.M.|author-link13=Jane El-Dahr |display-authors= 4 |title=The severity of autism is associated with toxic metal body burden and red blood cell glutathione levels|volume=2009|page=532640|doi=10.1155/2009/532640|journal=Journal of Toxicology|pmid=20107587|doi-access=free}}</ref><ref>{{cite journal|pmc=2774660|last1=Adams|first1=J.B.|last2=Baral|first2=M.|last3=Geis|first3=E.|last4=Mitchell|first4=J.|last5=Ingram|first5=J.|last6=Hensley|first6=A.|last7=Zappia|first7=I.|last8=Newmark|first8=S.|last9=Gehn|first9=E.|last10=Rubin|first10=R.A.|last11=Mitchell|first11=K.|last12=Bradstreet|first12=J.|last13=El-Dahr|first13=J. |display-authors= 4 |title=Safety and efficacy of oral DMSA therapy for children with autism spectrum disorders: Part A - Medical results|volume=9|page=16|doi=10.1186/1472-6904-9-16|journal=BMC Clinical Pharmacology|year=2009|pmid=19852789 |doi-access=free }}</ref> | |||
In 1998, the U.S. ] (FTC) charged that the web site of the American College for Advancement in Medicine (ACAM) and a brochure they published had made false or unsubstantiated claims. In December 1998, the FTC announced that it had secured a consent agreement barring ACAM from making unsubstantiated advertising claims that chelation therapy is effective against atherosclerosis or any other disease of the circulatory system.<ref>{{cite web|url=http://www.ftc.gov/os/caselist/c3882.shtm|title=American College for Advancement in Medicine, File No. 962 3147, Docket No. C-3882|publisher=Federal Trade Commission|accessdate=2007-11-11}}</ref><ref>{{cite web|url=http://www.quackwatch.org/02ConsumerProtection/ftcchelation.html||date=], ]|title=Medical Association Settles False Advertising Charges Over Promotion of 'Chelation Therapy'|publisher=Quackwatch|accessdate=2007-11-11}}</ref> | |||
== |
== See also == | ||
* ] | |||
* ] | |||
== References == | |||
The ] (ACAM), a not-for-profit 501(c)(6) organization which promotes chelation therapy, claims that 800,000 patient visits for chelation therapy, with an average of 40 visits per patient, were made in the United States in 1997.<ref>{{cite press release|url=http://web.archive.org/web/20070204053351/http://www.acam.org/press_releases/20020814.htm|title=Physician Group Backs New NIH Chelation Therapy Study For Heart Disease|publisher=American College for Advancement in Medicine|date=], ]|accessdate=2007-11-11}}</ref> | |||
{{reflist|30em}} | |||
== External links == | |||
== Side effects and safety concerns == | |||
* - ] | |||
There is a low occurrence of side effects when chelation is used at the dose and infusion rates approved by the U.S. ]. A burning sensation at the site of delivery into the vein is common. Rarer side effects include fever, headache, nausea, stomach upset, vomiting, a drop in blood pressure, and ]. Kidney toxicity is a safety concern, but a rare occurrence. When EDTA is not administered correctly, more serious side effects can occur.<ref name=NCCAMQA/> | |||
Chelation therapy can be hazardous. In August 2005, botched chelation therapy killed a 5-year-old autistic boy, a nonautistic child died in February 2005, and a nonautistic adult died in August 2003. These deaths were due to ] caused by ] during chelation therapy.<ref name=hypocalcemia>{{cite journal |journal=Pediatrics |date=2006 |volume=118 |issue=2 |pages=e534-6 |title= Deaths resulting from hypocalcemia after administration of edetate disodium: 2003–2005 |author= Brown MJ, Willis T, Omalu B, Leiker R |doi=10.1542/peds.2006-0858 |pmid=16882789 |url=http://pediatrics.aappublications.org/cgi/content/full/118/2/e534}}</ref> | |||
==References== | |||
{{reflist|2}} | |||
==External links== | |||
* "Chelation Therapy: Unproven Claims and Unsound Theories" by Sam Green | |||
* JAMA and Archives Journals (2008, January 8). Autism: Removing Thimerosal From Vaccines Did Not Reduce Autism Cases In California, Report Finds. ScienceDaily. Retrieved January 9, 2008, from http://www.sciencedaily.com /releases/2008/01/080107181551.htm | |||
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Latest revision as of 14:25, 6 November 2024
Medical procedure to remove heavy metals from the body Medical interventionChelation therapy | |
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Two molecules of deferasirox, an orally administered chelator, binding iron. Deferasirox is used in the treatment of transfusional iron overload in people with thalassemia. | |
[edit on Wikidata] |
Chelation therapy is a medical procedure that involves the administration of chelating agents to remove heavy metals from the body. Chelation therapy has a long history of use in clinical toxicology and remains in use for some very specific medical treatments, although it is administered under very careful medical supervision due to various inherent risks, including the mobilization of mercury and other metals through the brain and other parts of the body by the use of weak chelating agents that unbind with metals before elimination, exacerbating existing damage. To avoid mobilization, some practitioners of chelation use strong chelators, such as selenium, taken at low doses over a long period of time.
Chelation therapy must be administered with care as it has a number of possible side effects, including death. In response to increasing use of chelation therapy as alternative medicine and in circumstances in which the therapy should not be used in conventional medicine, various health organizations have confirmed that medical evidence does not support the effectiveness of chelation therapy for any purpose other than the treatment of heavy metal poisoning. Over-the-counter chelation products are not approved for sale in the United States.
Medical uses
Chelation therapy is the preferred medical treatment for metal poisoning, including acute mercury, iron (including in cases of sickle-cell disease and thalassemia), arsenic, lead, uranium, plutonium and other forms of toxic metal poisoning. The chelating agent may be administered intravenously, intramuscularly, or orally, depending on the agent and the type of poisoning.
Chelating agents
There are a variety of common chelating agents with differing affinities for different metals, physical characteristics, and biological mechanism of action. For the most common forms of heavy metal intoxication – lead, arsenic, or mercury – a number of chelating agents are available. Dimercaptosuccinic acid (DMSA) has been recommended by poison control centers around the world for the treatment of lead poisoning in children. Other chelating agents, such as 2,3-dimercaptopropanesulfonic acid (DMPS) and alpha lipoic acid (ALA), are used in conventional and alternative medicine. Some common chelating agents are ethylenediaminetetraacetic acid (EDTA), 2,3-dimercaptopropanesulfonic acid (DMPS), and thiamine tetrahydrofurfuryl disulfide (TTFD). Calcium-disodium EDTA and DMSA are only approved for the removal of lead by the Food and Drug Administration while DMPS and TTFD are not approved by the FDA. These drugs bind to heavy metals in the body and prevent them from binding to other agents. They are then excreted from the body. The chelating process also removes vital nutrients such as vitamins C and E, therefore these must be supplemented.
The German Environmental Agency (Umweltbundesamt) listed DMSA and DMPS as the two most useful and safe chelating agents available.
Chelator | Used in |
---|---|
Dimercaprol (British anti-Lewisite; BAL) |
|
Dimercaptosuccinic acid (DMSA) | |
Dimercapto-propane sulfonate (DMPS) |
|
Penicillamine | Mainly in:
Occasionally adjunctive therapy in: |
Ethylenediamine tetraacetic acid (calcium disodium versenate) (CaNa2-EDTA) | |
Deferoxamine, Deferasirox and Deferiprone |
|
Side effects
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|
When used properly in response to a diagnosis of harm from metal toxicity, side effects of chelation therapy include dehydration, low blood calcium, harm to kidneys, increased enzymes as would be detected in liver function tests, allergic reactions, and lowered levels of dietary elements. When administered inappropriately, there are the additional risks of hypocalcaemia (low calcium levels), neurodevelopmental disorders, and death.
History
Chelation therapy can be traced back to the early 1930s, when Ferdinand Münz, a German chemist working for I.G. Farben, first synthesized ethylenediaminetetraacetic acid (EDTA). Munz was looking for a replacement for citric acid as a water softener. Chelation therapy itself began during World War II when chemists at the University of Oxford searched for an antidote for lewisite, an arsenic-based chemical weapon. The chemists learned that EDTA was particularly effective in treating lead poisoning.
Following World War II, chelation therapy was used to treat workers who had painted United States naval vessels with lead-based paints. In the 1950s, Norman Clarke Sr. was treating workers at a battery factory for lead poisoning when he noticed that some of his patients had improved angina pectoris following chelation therapy. Clarke subsequently administered chelation therapy to patients with angina pectoris and other occlusive vascular disease and published his findings in The American Journal of the Medical Sciences in December 1956. He hypothesized that "EDTA could dissolve disease-causing plaques in the coronary systems of human beings." In a series of 283 patients treated by Clarke et al. From 1956 to 1960, 87% showed improvement in their symptomatology. Other early medical investigators made similar observations of EDTA's role in the treatment of cardiovascular disease (Bechtel, 1956; Bessman, 1957; Perry, 1961; Szekely, 1963; Wenig, 1958: and Wilder, 1962).
In 1973, a group of practicing physicians created the Academy of Medical Preventics (now the American College for Advancement in Medicine). The academy trains and certifies physicians in the safe administration of chelation therapy. Members of the academy continued to use EDTA therapy for the treatment of vascular disease and developed safer administration protocols.
In the 1960s, BAL was modified into DMSA, a related dithiol with far fewer side effects. DMSA quickly replaced both BAL and EDTA as the primary treatment for lead, arsenic and mercury poisoning in the United States. Esters of DMSA have been developed which are reportedly more effective; for example, the monoisoamyl ester (MiADMSA) is reportedly more effective than DMSA at clearing mercury and cadmium. Research in the former Soviet Union led to the introduction of DMPS, another dithiol, as a mercury-chelating agent. The Soviets also introduced ALA, which is transformed by the body into the dithiol dihydrolipoic acid, a mercury- and arsenic-chelating agent. DMPS has experimental status in the United States, while ALA is a common nutritional supplement.
Since the 1970s, iron chelation therapy has been used as an alternative to regular phlebotomy to treat excess iron stores in people with haemochromatosis. Other chelating agents have been discovered. They all function by making several chemical bonds with metal ions, thus rendering them much less chemically reactive. The resulting complex is water-soluble, allowing it to enter the bloodstream and be excreted harmlessly.
Calcium-disodium EDTA chelation has been studied by the U.S. National Center for Complementary and Alternative Medicine for treating coronary disease. In 1998, the U.S. Federal Trade Commission (FTC) pursued the American College for Advancement in Medicine (ACAM), an organization that promotes "complementary, alternative and integrative medicine" over the claims made regarding the treatment of atherosclerosis in advertisements for EDTA chelation therapy. The FTC concluded that there was a lack of scientific studies to support these claims and that the statements by the ACAM were false. In 1999, the ACAM agreed to stop presenting chelation therapy as effective in treating heart disease, avoiding legal proceedings. In 2010 the U.S. Food and Drug Administration (FDA) warned companies who sold over-the-counter (OTC) chelation products and stated that such "products are unapproved drugs and devices and that it is a violation of federal law to make unproven claims about these products. There are no FDA-approved OTC chelation products."
Controversies
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In 1998, the U.S. Federal Trade Commission (FTC) charged that the web site of the American College for Advancement in Medicine (ACAM) and a brochure they published had made false or unsubstantiated claims. In December 1998, the FTC announced that it had secured a consent agreement barring ACAM from making unsubstantiated advertising claims that chelation therapy is effective against atherosclerosis or any other disease of the circulatory system.
In August 2005, doctor error led to the death of a five-year-old boy with autism who was undergoing chelation therapy. Others, including a three-year-old non-autistic girl and a non-autistic adult, have died while undergoing chelation therapy. These deaths were due to cardiac arrest caused by hypocalcemia during chelation therapy. In two of the cases, hypocalcemia appears to have been caused by the administration of Na2EDTA (disodium EDTA) and in the third case the type of EDTA was unknown. Only the three-year-old girl had been found to have an elevated blood lead level and resulting low iron levels and anemia, which is the conventional medical cause for administration of chelation therapy.
According to protocol, EDTA should not be used in the treatment of children. More than 30 deaths have been recorded in association with IV-administered disodium EDTA since the 1970s.
Use in alternative medicine
In alternative medicine, some practitioners claim chelation therapy can treat a variety of ailments, including heart disease and autism. The use of chelation therapy by alternative medicine practitioners for behavioral and other disorders is considered pseudoscientific; there is no proof that it is effective. Chelation therapy prior to heavy metal testing can artificially raise urinary heavy metal concentrations ("provoked" urine testing) and lead to inappropriate and unnecessary treatment. The American College of Medical Toxicology and the American Academy of Clinical Toxicology warn the public that chelating drugs used in chelation therapy may have serious side effects, including liver and kidney damage, blood pressure changes, allergies and in some cases even death of the patient.
Cancer
The American Cancer Society says of chelation therapy: "Available scientific evidence does not support claims that it is effective for treating other conditions such as cancer. Chelation therapy can be toxic and has the potential to cause kidney damage, irregular heartbeat, and even death."
Cardiovascular disease
According to the findings of a 1997 systematic review, EDTA chelation therapy is not effective as a treatment for coronary artery disease and this use is not approved in the United States by the US Food and Drug Administration (FDA).
The American Heart Association stated in 1997 that there is "no scientific evidence to demonstrate any benefit from this form of therapy." The FDA, the National Institutes of Health (NIH) and the American College of Cardiology "all agree with the American Heart Association" that "there have been no adequate, controlled, published scientific studies using currently approved scientific methodology to support this therapy for cardiovascular disease." They speculate that any improvement among heart patients undergoing chelation therapy can be attributed to the placebo effect and generally recommended lifestyle changes such as "quitting smoking, losing weight, eating more fruits and vegetables, avoiding foods high in saturated fats and exercising regularly." They also are concerned that patients could put off proven treatments for heart disease like drugs or surgery.
A systematic review published in 2005 found that controlled scientific studies did not support chelation therapy for heart disease. It found that very small trials and uncontrolled descriptive studies have reported benefits while larger controlled studies have found results no better than placebo.
In 2009, the Montana Board of Medical Examiners issued a position paper concluding that "chelation therapy has no proven efficacy in the treatment of cardiovascular disease, and in some patients could be injurious."
The U.S. National Center for Complementary and Alternative Medicine (NCCAM) conducted a trial on the chelation therapy's safety and efficacy for patients with coronary artery disease. NCCAM Director Stephen E. Straus cited the "widespread use of chelation therapy in lieu of established therapies, the lack of adequate prior research to verify its safety and effectiveness, and the overall impact of coronary artery disease" as factors motivating the trial. The study has been criticized by some who said it was unethical, unnecessary and dangerous, and that multiple studies conducted prior to it demonstrated that the treatment provides no benefit.
The US National Center for Complementary and Alternative Medicine began the Trial to Assess Chelation Therapy (TACT) in 2003. Patient enrollment was to be completed around July 2009 with final completion around July 2010, but enrollment in the trial was voluntarily suspended by organizers in September 2008 after the Office for Human Research Protections began investigating complaints such as inadequate informed consent. Additionally, the trial was criticized for lacking prior Phase I and II studies, and critics summarized previous controlled trials as having "found no evidence that chelation is superior to placebo for treatment of CAD or PVD." The same critics argued that methodological flaws and lack of prior probability made the trial "unethical, dangerous, pointless, and wasteful." The American College of Cardiology supported the trial and research to explore whether chelation therapy was effective in treating heart disease. Evidence of insurance fraud and other felony convictions among (chelation proponent) investigators further undermined the credibility of the trial.
The final results of TACT were published in November 2012. The authors concluded that disodium EDTA chelation "modestly" reduced the risk of adverse cardiovascular outcomes among stable patients with a history of myocardial infarction. The study also showed a "marked" reduction in cardiovascular events in diabetic patients treated with EDTA chelation. An editorial published in the Journal of the American Medical Association said that "the study findings may provide novel hypotheses that merit further evaluation to help understand the pathophysiology of secondary prevention of vascular disease." Critics of the study characterized the study as showing no support for the use of chelation therapy in coronary heart disease, particularly the claims to reduce the need for coronary artery bypass grafting (CABG, pronounced "cabbage").
Autism
Main article: Thiomersal controversyQuackwatch says that autism is one of the conditions for which chelation therapy has been falsely promoted as effective, and practitioners falsify diagnoses of metal poisoning to trick parents into having their children undergo the risky process. As of 2008, up to 7% of children with autism worldwide had been subjected to chelation therapy. The death of two children in 2005 was caused by the administration of chelation treatments, according to the American Center for Disease Control. One of them had autism. Parents either have a doctor use a treatment for lead poisoning, or buy unregulated supplements, in particular DMSA and lipoic acid. Aspies For Freedom, an autism rights organization, considers this use of chelation therapy unethical and potentially dangerous. There is little to no credible scientific research that supports the use of chelation therapy for the effective treatment of autism.
See also
References
- ^ Aaseth, Jan; Crisponi, Guido; Anderson, Ole (2016). Chelation Therapy in the Treatment of Metal Intoxication. Academic Press. p. 388. ISBN 978-0-12-803072-1.
- "Chelation: Therapy or "Therapy"?". poison.org. National Capital Poison Center. 6 May 2013 . Retrieved 9 October 2013.
- ^ Atwood, K.C. IV; Woeckner, E.; Baratz, R.S.; Sampson, W.I. (2008). "Why the NIH Trial to Assess Chelation Therapy (TACT) should be abandoned". Medscape Journal of Medicine. 10 (5): 115. PMC 2438277. PMID 18596934.
- ^ "Chelation Therapy". American Cancer Society. 1 November 2008. Archived from the original on 5 July 2010. Retrieved 14 September 2013.
- "Deaths Associated with Hypocalcemia from Chelation Therapy - Texas, Pennsylvania, and Oregon, 2003-2005". www.cdc.gov. Retrieved 2016-10-13.
- ^ Food and Drug Administration (FDA) (14 October 2010). "FDA issues warnings to marketers of unapproved 'chelation' products" (Press release). Archived from the original on January 11, 2017.
- Flora, Swaran J. S.; Pachauri, Vidhu (2010-06-28). "Chelation in Metal Intoxication". International Journal of Environmental Research and Public Health. 7 (12): 2745–2788. doi:10.3390/ijerph7072745. PMC 2922724. PMID 20717537.
- Fortin, Patricia M.; Fisher, Sheila A.; Madgwick, Karen V.; Trivella, Marialena; Hopewell, Sally; Doree, Carolyn; Estcourt, Lise J. (May 8, 2018). "Interventions for improving adherence to iron chelation therapy in people with sickle cell disease or thalassaemia". The Cochrane Database of Systematic Reviews. 2018 (5): CD012349. doi:10.1002/14651858.CD012349.pub2. ISSN 1469-493X. PMC 5985157. PMID 29737522.
- Hider, Robert C.; Kong, Xiaole (2013). "Chapter 8. Iron: Effect of Overload and Deficiency". In Astrid Sigel, Helmut Sigel and Roland K. O. Sigel (ed.). Interrelations between Essential Metal Ions and Human Diseases. Metal Ions in Life Sciences. Vol. 13. Springer. pp. 229–294. doi:10.1007/978-94-007-7500-8_8. ISBN 978-94-007-7499-5. PMID 24470094.
- Flora, Govinder; Mittal, Megha; Flora, Swaran J. S. (2015-01-01), Flora, S. J. S. (ed.), "26 - Medical Countermeasures—Chelation Therapy", Handbook of Arsenic Toxicology, Oxford: Academic Press, pp. 589–626, ISBN 978-0-12-418688-0, retrieved 2020-12-07
- Chisolm, J.J. Jr. (2000). "Safety and efficacy of meso-2,3-dimercaptosuccinic acid (DMSA) in children with elevated blood lead concentrations". Journal of Toxicology: Clinical Toxicology. 38 (4): 365–75. doi:10.1081/CLT-100100945. PMID 10930052. S2CID 21793727.
- Bridges, Sarah (January 2006). "The promise of chelation". Mothering. No. 134. pp. 54–61.
- Kommission Human-Biomonitoring des Umweltbundesamtes (1999). "Bekanntmachung des Umweltbundesamtes Einsatz von Chelatbildnern in der Umweltmedizin? Stellungnahme der Kommission 'Human-Biomonitoring' des Umweltbundesamtes" [Notice of the Federal Environmental Agency use of chelating agents in environmental medicine? Opinion of the Commission 'Human biomonitoring' of the German Federal Environment Agency]. Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz (in German). 42 (10): 823–4. doi:10.1007/s001030050288. S2CID 30922256.
- ^ Masters, Susan B.; Trevor, Anthony J.; Katzung, Bertram G. (2008). Katzung & Trevor's Pharmacology: Examination & Board Review (8th ed.). McGraw Hill Medical. pp. 481–3. ISBN 978-0-07-148869-3.
- Crisponi, Guido; Nurchi, Valeria M.; Lachowicz, Joanna (2019). "Chapter 3. Iron Chelation for Iron Overload in Thalassemia". In Sigel, Astrid; Freisinger, Eva; Sigel, Roland K. O.; Carver, Peggy L. (eds.). Essential Metals in Medicine:Therapeutic Use and Toxicity of Metal Ions in the Clinic. Vol. 19. Berlin: de Gruyter GmbH. pp. 49–86. doi:10.1515/9783110527872-009. ISBN 978-3-11-052691-2. PMID 30855104. S2CID 73727755.
{{cite book}}
:|journal=
ignored (help) - ^ American College of Medical Toxicology; American Academy of Clinical Toxicology (February 2013), "Five Things Physicians and Patients Should Question", Choosing Wisely: an initiative of the ABIM Foundation, American College of Medical Toxicology and American Academy of Clinical Toxicology, retrieved 5 December 2013, which cites
- Kosnett, M J (2010). "Chelation for Heavy Metals (Arsenic, Lead, and Mercury): Protective or Perilous?". Clinical Pharmacology & Therapeutics. 88 (3): 412–415. doi:10.1038/clpt.2010.132. ISSN 0009-9236. PMID 20664538. S2CID 28321495.
- Medical Letter consultants (September 20, 2010). "Nonstandard uses of chelation therapy". The Medical Letter on Drugs and Therapeutics. 52 (1347): 75–6. PMID 20847718.
- Food and Drug Administration (14 October 2010). "Consumer Updates - FDA Warns Marketers of Unapproved 'Chelation' Drugs". fda.gov. Retrieved 3 July 2014.
- ^ "Chemistry in its element: compounds". Royal Society of Chemistry. Retrieved 30 June 2014.
- Grebe, Heidi Braun; Gregory, Philip J. (2002). "Inhibition of Warfarin Anticoagulation Associated with Chelation Therapy". Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy. 22 (8). Wiley: 1067–1069. doi:10.1592/phco.22.12.1067.33602. ISSN 0277-0008. PMID 12173793.
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{{cite press release}}
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However, given the significant methodological limitations of these studies, the research reviewed here does not support the use of chelation as a treatment for ASD
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