释义 |
DictionarySeechelationEncyclopediaSeetherapychelation therapy
Chelation Therapy DefinitionChelation therapy is an intravenous treatment designed to bind heavy metals in the body in order to treat heavy metal toxicity. Proponents claim it also treats coronary artery disease and other illnesses that may be linked to damage from free radicals (reactive molecules).PurposeThe benefits of EDTA chelation for the treatment of lead poisoning and excessively high calcium levels are undisputed. The claims of benefits for those suffering from atherosclerosis, coronary artery disease, and other degenerative diseases are more difficult to prove. Reported uses for chelation therapy include treatment of angina, gangrene, arthritis, multiple sclerosis, Parkinson's disease, psoriasis, and Alzheimer's disease. Improvement is also claimed for people experiencing diminished sight, hearing, smell, coordination, and sexual potency.DescriptionOriginsThe term chelation is from the Greek root word "chele," meaning "claw." Chelating agents, most commonly diamine tetraacetic acid (EDTA), were originally designed for industrial applications in the early 1900s. It was not until the World War II era that the potential for medical therapy was realized. The initial intent was to develop antidotes to poison gas and radioactive contaminants. The need for widespread therapy of this nature did not materialize, but more practical uses were found for chelation. During the following decade, EDTA chelation therapy became standard treatment for people suffering from lead poisoning. Patients who had received this treatment claimed to have other health improvements that could not be attributed to the lead removal only. Especially notable were comments from those who had previously suffered from intermittent claudication and angina. They reported suffering less pain and fatigue, with improved endurance, after chelation therapy. These reports stimulated further interest in the potential benefits of chelation therapy for people suffering from atherosclerosis and coronary artery disease.If the preparatory examination suggests that there is a condition that could be improved by chelation therapy, and there is no health reason why it shouldn't be used, then the treatment can begin. The patient is generally taken to a comfortable treatment area, sometimes in a group location, and an intravenous line is started. A solution of EDTA together with vitamins and minerals tailored for the individual patient is given. Most treatments take three to four hours, as the infusion must be given slowly in order to be safe. The number of recommended treatments is usually between 20 and 40. They are given one to three times a week. Maintenance treatments can then be given at the rate of once or twice a month. Maximum benefits are reportedly attained after approximately three months after a treatment series. The cost of therapy is considerable, but it is a fraction of the cost of an expensive medical procedure like cardiac bypass surgery. Intravenous vitamin C and mercury chelation therapies are also offered.PreparationsA candidate for chelation therapy should initially have a thorough history and physical to define the type and extent of clinical problems. Laboratory tests will be done to determine whether there are any conditions present that would prevent the use of chelation. Patients who have preexisting hypocalcemia, poor liver or kidney function, congestive heart failure, hypoglycemia, tuberculosis, clotting problems, or potentially allergic conditions are at higher risk for complications from chelation therapy. A Doppler ultrasound may be performed to determine the adequacy of blood flow in different regions of the body.PrecautionsIt is important for people who receive chelation therapy to work with medical personnel who are experienced in the use of this treatment. Treatment should not be undertaken before a good physical, lifestyle evaluation, history, and any laboratory tests necessary are performed. The staff must be forthcoming about test results and should answer any questions the patient may have. Evaluation and treatment should be individualized and involve assessment of kidney function before each treatment with chelation, since the metals bound by the EDTA are excreted through the kidneys.Although EDTA binds harmful, toxic metals like mercury, lead, and cadmium, it also binds some essential nutrients of the body, such as copper, iron, calcium, zinc, and magnesium. Large amounts of zinc are lost during chelation. Zinc deficiency can cause impaired immune function and other harmful effects. Supplements of zinc are generally given to patients undergoing chelation, but it is not known whether this is adequate to prevent deficiency. Also, chelation therapy does not replace proper nutrition, exercise, and appropriate medications or surgery for specific diseases or conditions.Key termsAngina — Chest pain caused by reduced oxygen to the heart.Atherosclerosis — Arterial disease characterized by fatty deposits on inner arterial walls.Hypocalcemia — Low blood calcium.Hypoglycemia — Low blood sugar.Intermittent claudication — Leg pain and weakness caused by walking.Thrombophlebitis — Inflammation of a vein together with clot formation.Side effectsSide effects of chelation therapy are reportedly unusual, but are occasionally serious. Mild reactions may include, but are not limited to, local irritation at the infusion site, skin reactions, nausea, headache, dizziness, hypoglycemia, fever, leg cramps, or loose bowel movements. Some of the more serious complications reported have included hypocalcemia, kidney damage, decreased clotting ability, anemia, bone marrow damage, insulin shock, thrombophlebitis with embolism, and even rare deaths. However, some doctors feel that the latter groups of complications occurred before the safer method currently used for chelation therapy was developed.Research and general acceptanceEDTA chelation is a highly controversial therapy. The treatment is approved by the United States Food and Drug Administration (FDA) for lead poisoning and seriously high calcium levels. However, for the treatment of atherosclerotic heart disease, EDTA chelation therapy is not endorsed by the American Heart Association (AHA), the FDA, the National Institutes of Health (NIH), or the American College of Cardiology. The AHA reports that there are no adequate, controlled, published scientific studies using currently approved scientific methods to support this therapy for the treatment of coronary artery disease. However, a pooled analysis from the results of over 70 studies showed positive results in all but one.ResourcesOrganizationsThe American College for Advancement in Medicine (ACAM). 23121 Verdugo Dr., Suite 204, Laguna Hills, CA 92653. (714) 583-7666.American Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-630 or (800) 242-8721. inquire@heart.org. http://www.americanheart.org.OtherCranton, Elmer. Chelation therapy. 1999. 〈http://www.drcranton.com/chelation.html〉.Green, Saul. Quackwatch: Chelation therapy. 2000. http://www.quackwatch.com/01QuackeryRelatedTopics/chelation.html.chelation therapy The use of a chemical to bind a substance and thereby inactivate it. Fringe medicine Chelation is said to remove toxins and metabolic wastes from the blood for various conditions—e.g., coronary heart disease. Fringe medicine Some alternative practitioners believe that Ca2+ can be chelated from atherosclerotic plaques and, by extension, is an alternative to CABG and angioplasty. Anecdotal (fringe) reports imply that chelation may be useful for arthritis and connective tissue diseases, improving vision, hearing, sense of smell and memory; it is also believed by some practitioners of alternative healthcare to reverse the effects of degenerative diseases linked to poor circulation, cataracts, DM, emphysema, gallstones, hypertension, osteoporosis, Parkinson’s disease, renal disease and strokes. Toxicology The only FDA-approved indication for EDTA chelation is for treating heavy metal (e.g., lead, mercury) poisoning. Adverse effects Anorexia, headaches, bone marrow suppression, arrhythmias, haemolytic anaemia, joint pain, muscle spasms, N&V, osteoporosis, phlebitis, renal damage and failure, death.chelation therapy The use of a chemical to bind and thereby inactivate a substance. Toxicology The only approved indication for EDTA chelation is for treating heavy metal–eg lead, mercury poisoning |