Chelation therapy is a technique for removing certain toxic chemicals, such as lead, arsenic, and other heavy metals, from the body. For more than forty years, chelation therapy has been an effective method of treating lead poisoning and has been approved by the FDA for this use. At this time, there is no scientific evidence that chelation therapy is of value for cancer or any conditions other than heavy-metal poisoning. Chelating drugs can be taken orally or given as injections into muscles or veins. Often, chelation therapy involves an infusion, during which the drug drips into the vein over the course of three or four hours.
Some patients undergo three or four infusions per week for up to ten weeks.
Once the metal binds to the chelate, the resulting substance becomes less toxic and can be more easily passed out of the body in the urine. The drug EDTA also binds with calcium. Calcium is one of the substances that can build up in plaques, which are stiff, fatty patches that can cause narrowing of blood vessels, resulting in heart disease or stroke. The resulting improvement in blood flow is claimed to help patients to avoid bypass surgery or other procedures to unblock blood vessels. More recently, advocates have come to believe that removing excess iron and copper through chelation blocks the production of free radicals.