Chelation Therapy for Autism: Purpose and Risks

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Chelation therapy for autism involves the use of drugs to clear heavy metals from the body, which some people believe causes autism. It is an alternative therapy that has little proven benefit but one that can cause potential harm, including kidney damage, seizures, palpitations, and even death.

Chelation therapy was popularized during the late 1990s and early 2000s when a series of studies suggested a link between autism and a mercury-based preservative called thimerasol used in the measle-mumps-rubella (MWR) vaccine. The claims have since been debunked.

Female doctor and boy with stethoscope in medical practice
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Purpose and Theory

Chelation therapy is approved by the U.S. Food and Drug Administration (FDA) for the treatment of severe hemochromatosis (iron overload) as well as lead, mercury, arsenic, and other types of heavy metal poisoning. It involves the use of chelating drugs that bind to the metal so that is it cleared from the body in urine.

Chelation therapy was first proposed for the treatment of autism during the 1990s after physician and anti-vaccine advocate Andrew Wakefield published a series of case studies in the Lancet suggesting a link between autism and the MMR vaccine.

Wakefield's claims seemed so overwhelmingly conclusive that several research teams in the United Kingdom and Europe started investigating whether thimerasol—or specifically mercury contained in thimerasol—was the culprit.

Although studies quickly debunked the association, the Centers for Disease Control and Prevention (CDC) and the American Pediatric Association (APA) issued a statement in 1999 recommending the discontinuation of thimerosal-containing vaccines. To some, this was a confirmation that thimerasol was dangerous and solidified it as the "cause" of autism.

However, in 2010, the Sunday Times in London published evidence that Wakefield falsified the study, leading to the retraction of the Lancet study and, soon after, the removal of Wakefield from the medical registry in the United Kingdom.

By this time, chelation therapy had already worked its way into the public's consciousness as a means of treating—or even curing—autism. This not only included the chelation of mercury but other heavy metals as well.

Rationale for Use

Chelation therapy is not an approved treatment for autism and is regarded by most as an unendorsed alternative therapy.

Even so, studies have shown that between 6% and 11% of families of children with autism in countries like the United States, Canada, and Australia, have sought chelation therapy to treat or cure autism.

The rationale for the use is based on the fact that excess mercury and other heavy metals can interfere with the development of the brain and nervous system in children. It is thought by some that the neurodevelopmental problems associated with autism are not unlike those of mercury poisoning and, as such, may benefit from the same treatment approach.

Others contend that people with autism have a decreased ability to excrete heavy metals from their bodies, leading to toxic accumulation even with minimal exposure to metals like mercury or lead. More research is needed.

What Is Involved

Irrespective of its intended use, chelation therapy starts with a provocation test in which the person is given a chelating drug. An analysis of their urine will show whether there are unusually high levels of heavy metal being excreted.

If the heavy metal concentration falls within the toxic range, chelation therapy can be delivered either orally (by mouth), intravenously (into a vein), or by intramuscular injection (into a large muscle). The medications are delivered in a hospital setting so that the patient can be monitored for side effects.

Different chelating agents have been proposed for the treatment of autism, none of which have been approved by the FDA for such use.

These include chelating agents like:

  • Dimercaptosuccinic acid (DMSA), used for mercury, lead, and arsenic poisoning
  • Sodium dimercaptopropanesulphonate (DMPS), used for mercury and arsenic poisoning and copper overload (Whipple's disease)
  • Edetate disodium (EDTA), used for mercury, lead, and cadmium poisoning as well as calcium overload (hypercalcemia)
  • Edetate calcium disodium (ECD), used for lead poisoning

These drugs are available by prescription only. There are no over-the-counter (OTC) chelating drugs approved for use in the United States. There is also no recommended dose or guidelines for the appropriate use of chelation in people with autism.

When used for heavy metal poisoning, chelating agents like DMSA are given orally every eight hours for three days, while agents like EDTA are given intravenously every six hours for five days.

Side Effects and Risks

Even when used appropriately, chelation therapy can have side effects ranging from mild to life-threatening. Possible side effects of EDTA, one of the most commonly used chelating drugs, include:

In rare cases, chelating drugs like EDTA have been known to cause acute kidney failure, severe hypotension (low blood pressure), shock, multi-organ failure, and death.

In 2006, a child with autism died after receiving botched chelation therapy.

Does Chelation Therapy Work for Autism?

In 2015, a comprehensive analysis of studies published in the Cochrane Database of Systematic Reviews concluded that there is no clinical evidence that chelation therapy is effective for the treatment of autism. Moreover, due to the risk of kidney failure and other complications, including death, the risks of chelation for autism far outweigh any potential benefit.

The Association for Science in Autism Treatment further states: "Chelation is not an intervention that should be considered for autism, and its use poses great risk to individuals with autism."

Summary

Chelation therapy for autism is an alternative therapy said to treat autism by removing heavy metals, like mercury, from the body with drugs. There is no evidence that it works. Possible risks include irregular heartbeats, seizures, kidney failure, and death.

Chelation therapy should never be used for the treatment of autism.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Lisa Jo Rudy

By Lisa Jo Rudy
Rudy is a writer, consultant, author, and advocate who specializes in autism. Her work has appeared in The New York Times and Autism Parenting Magazine.