What Is Chelation Therapy?

A Treatment for Metal Poisoning, With Other Controversial Uses

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Chelation therapy is a treatment primarily used for metal poisoning, but it is also an alternative treatment option for other conditions. It's based on the process of chelation, in which chemicals are used to remove heavy metals and other substances from the body.

Although chelation was originally used to treat conditions like lead poisoning, chelation therapy is now claimed to protect against heart disease and other major health problems.

A doctor performing chelation therapy
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The word chelation is derived from the Greek word chelos, which means claw. The term refers to how a bodily metal like iron binds in a pincer-like manner to a chemical compound known as a chelating agent.

The first clinical use of chelation therapy was in 1956, where improvements were seen through therapy in 19 out of 20 lead-poisoned patients with severe angina. Since then, its efficacy for metal poisoning is well established, but there has been limited support and studies for its use in treating other conditions.


In chelation therapy, a chelating agent is introduced into the body through an intravenous (IV) drip or oral pill. Once it enters the bloodstream, the agent binds to certain molecules (such as metals or minerals) and is removed from the body through urination, carrying those molecules with it.

One of the most common chelating agents used in chelation therapy is ethylene diamine tetra-acetic acid (EDTA). EDTA is known to remove substances such as lead, iron, copper, and calcium from the blood.

Other chelating agents also used include:

  • Dimercaprol: Dimercaprol is commonly used to treat arsenic, gold, copper, and mercury poisoning, as well as severe cases of Wilson's disease.
  • Succimer: Succimer is an oral chelating agent mainly used to treat lead poisoning, especially in children. Succimer also treats cadmium, mercury, and arsenic poisoning as well.
  • Deferoxamine: Deferoxamine is primarily used to treat iron overload but also treats zinc and copper poisoning.
  • Penicillamine: Penicillamine is used to decrease copper stores in Wilson's disease and treat immune disorders such as rheumatoid arthritis and scleroderma.
  • Deferasirox: Deferasirox is used to treat lead poisoning. Deferasirox also binds to zinc and copper, but to a lesser extent.

It should be noted that FDA-approved chelating agents are available solely by prescription for specific circumstances, such as in the case of lead poisoning or iron overload.

Conditions Treated

Although the FDA has only approved prescription chelation therapy for metal poisoning, some health professionals have used chelation therapy for other ailments.

A common belief of proponents of chelation therapy is that it can aid in treating atherosclerosis (i.e., hardening of the arteries). Since calcium deposits are found in artery-clogging plaques, some practitioners argue that using chelation therapy to remove calcium deposits can restore healthy blood flow in the arteries.

Some also suggest that EDTA can act as an antioxidant and protect against the damaging effects of chronic inflammation. To that end, chelation therapy is also used to treat osteoarthritis and other inflammation-related conditions.

In addition, chelation therapy is sometimes used to treat the following health issues:

Who Does It

Any licensed physician can perform chelation therapy on a patient. However, chelation therapy for uses other than metal toxicity is not conventionally taught in medical school, and physicians who perform it generally are naturopathic doctors or medical doctors who receive specialized training for it.


The scientific support for chelation therapy's benefits for health conditions other than metal poisoning is limited. There is a consensus that much more research is needed in this area.

For example, one comprehensive review of studies on chelation therapy and heart health concluded that there was insufficient evidence to determine whether chelation therapy is effective or not.

Some believe chelation therapy can help those with autism, as some research has implied a possible link between autism and increased toxic metal levels in the body. But in one systematic review that explored this possible link, it was found that there was no evidence from clinical trials that supports chelation therapy as a viable treatment option.

Past research has discouraged the use of chelation therapy because of its potential to cause adverse effects and indirect harm to patients.

However, there's some evidence that chelation therapy may be beneficial in certain instances, like for those who have suffered a heart attack.

In one of the most notable studies in the history of chelation therapy, known as the Trial to Assess Chelation Therapy (TACT), researchers evaluated the effectiveness and safety of EDTA-based chelation therapy for those who experienced a heart attack.

TACT involved 1,708 participants and took ten years to complete, and revealed that chelation therapy might reduce the risk of issues such as stroke and hospitalization for angina.

However, there were several problems with the study that make its results somewhat questionable. One problem, in particular, was that many participants dropped out of the study, which could skew the results.

Further randomized trials will be necessary to assess whether chelation therapy may be helpful in people with heart disease, and the National Institutes of Health is currently funding more research in this area.

Side Effects & Safety Concerns

A major reason chelation therapy is not widely accepted for conditions other than metal poisoning is due to the risk of side effects, which is significant.

Side effects can especially occur when higher doses are used, and include:

  • Diarrhea
  • Weight loss
  • High blood pressure
  • Abdominal pain
  • Gastrointestinal disorders
  • Nausea
  • Skin rash
  • Vomiting
  • Flu-like symptoms

In some cases, chelation therapy may trigger serious side effects, such as kidney damage and dehydration. There's also concern that chelation therapy could remove calcium from healthy bones and other tissues.

A Word From Verywell

Chelation therapy has been effective in treating metal poisoning, but its efficacy in treating other conditions is unclear. Be sure you talk to your doctor and understand the risks of chelation therapy if you are interested in receiving it.

16 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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  4. National Institute of Diabetes and Digestive and Kidney Diseases. Deferoxamine.

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  13. Arora M, Reichenberg A, Willfors C, et al. Fetal and postnatal metal dysregulation in autismNat Commun. 2017. 1;8:15493 doi: 10.1038/ncomms15493

  14. National Center for Complementary and Integrative Health. Questions and answers: The NIH trials of EDTA chelation therapy for coronary heart disease.

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By Cathy Wong
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.