Chelation therapy side effects

I began chelation therapy without questioning what harmful side effects this might have. I was so relieved to have a reason for my ills beyond it s all in your head when I knew something was physically wrong with me I chelated seven days a week year round as it was the only way to keep myself out of bed. I did not know at the time how damaging it was or how hard it was on my adrenals and liver. 

Similar to the mustard agents, exposure prevention is the first line of defense against lewisite. Rapid decontamination is especially relevant to lewisite exposure due to the rapid development of pain (1-2 min) associated with lewisite exposure. Unlike other vesicants, an effective antidote for lewisite toxicity exists in the form of British anti-lewisite (BAL 2,3-dimercaptopropanol) which binds with arsenicals, thereby countering the lewisite-induced damage. Such chelation therapy is associated with notable side effects (e.g. renal effects) and requires carefiil medical management. More effective analogs of BAL have been developed with less significant side effects. 

Triethylene tetramine The copper-chelating agent triethylene tetramine (trientine) can be considered as an alternative therapy to penicillamine (J.M. Walshe, 1982). (389) The initial dose is 3-4 x 600 mg/day the recommended maintenance dose is 2 x 600 mg/day, administered about one hour before meals. The side effects are similar to those observed with penicillamine, but effi-... 

Iron removal Increased iron and ferritin levels are found in approx. 30% of patients with chronic hepatitis B or C. Several studies have shown that the success rate of interferon therapy is reduced in the presence of elevated liver iron values. This is attributed to the fact that iron overload inhibits not only lymphocyte proliferation, but also the function of killer cells and B cells as well as the production of antibodies. Iron plays a role in the formation of free radicals and the occurrence of dangerous lipid peroxidations, (s. pp 68, 401) Furthermore, iron, like oxygen radicals, promotes fibrogenesis. Iron removal leads to an improvement in laboratory parameters and better response to interferon-a therapy. (217, 243) On the other hand, the iron level is reduced as a result of successful IFN therapy. In the case of a higher serum iron status before the initiation of interferon therapy, venesections at one week intervals should be considered, if necessary until normal laboratory values (iron, ferritin, transferrin saturation) have been restored. During interferon therapy, a low-iron diet is advisable, as is the consumption of 2 x 1 cup of black tea (in the morning and at noon) to reduce iron absorption through chelate formation ( cheap, free of side effects and useful )- (s. p. 625) Silymarin also leads to iron mobilization due to chelate formation. 

Treatment of active, symptomatic Wilson s disease is aimed at increasing urine copper excretion to eliminate excess copper from tissue. The primary therapy for Wilson s disease involves chelating agents such as o-penicillamine and trientine, which is now more widely used because of its lower rate of side effects. In patients with minimal symptoms or in asymptomatic family members, zinc is used to competitively inhibit copper absorption from the intestinal tract. Lifelong therapy with one of these types of treatment is required and is usually successful in limiting further damage. 

It is axiomatic that the toxicity of the ligand selected for the treatment and any side effects, such as co-liberating essential metals during therapy, ought, collectively, to add up to less than the residual toxicity of the element that has been deposited in the body. However, factors other than simple toxicity or unpleasant side effects need to be considered. For example, about 90% of the lead accumulated in the human body is sequestered in non-toxic form in bone. Incautious chelation therapy with an agent like EDTA, or administration of large amounts of... 

The major side effect of chelation therapy, particularly with EDTA, is hypocalcaemia, a condition caused by too rapid administration of the chelator. The result is a rapid drop in the ionized calcium in the blood plasma that causes muscle and abdominal cramps, convulsions, and even death. The condition is usually controlled by infusion of calcium gluconate, or prevented when the metal to be removed complexes with a much higher stability constant with EDTA than that of the Ca-EDTA, by administration as the Ca-EDTA complex. 

Chelation therapy has found increased application during the last half of this century and so it is important to continue researching in order to extend its applicability, but especially to gain more knowledge of both the adverse as well as the beneficial effects of such therapy. Essentially the objective must be to optimize the treatment regime so that the best possible therapeutic effect is achieved with minimal adverse side effects. 

The chelation therapy mentioned above works by aiming to reduce BLLs by introducing agents such as DMSA (dimercaptosuc-cinic acid) and EDTA (calcium disodium) which bind to lead and thereby encourage its excretion in the urine. DMSA is particularly useful in yoimger children as it can be given by mouth, it is not without side effects however which include anorexia, nausea, vomiting and rashes. It is more commonly indicated in patients... 

The most commonly used chelation therapy agents in the United States today are EDTA and DMSA (or succimer). In addition, penicillamine (PCA) and BAL are used to chelate lead. Each of these agents has numerous disadvantages, ranging from undesirable methods of delivery (intramuscular injection of BAL and intravenous delivery of EDTA), to unpleasant side effects (typically nausea and vomiting), to chelation and increased excretion of necessary metals (e.g., iron and zinc) (Table XIX) (17, 207, 525). 

Dextran and its derivates have found some applications in the medical field. Dextran sulphate has anticoagulant properties similar to those of heparin. Recent studies show antiviral properties of the sulphate esters of dextran, particularly in the treatment of the human immunodeficiency virus.Oral dextran sulphate has been used in Japan against arteriosclerosis for 20 years without harmful side-effects. Mercaptodextran is discussed for therapy of acute heavy-metal poisoning because it has a higher affinity for heavy metal ions such as silver, mercuric, cupric and auric ions than most other thiols and chelating agents. The properties of mercaptodextran are of interest regarding environmental clean-up of heavy metal contaminations. ... 

Deferoxamine is the oldest of the chelation therapies, and is administered typically at 40mg/kg body weight, for 8-12 h, 4 days per week. However, some patients do not receive sufficient benefit from deferoxamine and develop cardiac iron overload and failure [S ]. More recently, orally bioavailable chelators, such as deferiprone and deferasirox, have become popular. However, the oral iron chelators have shown side effects that differ from those of deferoxamine. Deferiprone has proven to be more efficacious than deferasirox in several clinical trials, and is now routinely administered when deferoxamine treatment has failed. However, it is associated with agranulocytosis in about 1% of patients through an as yet undetermined mechanism and neutropenia more rarely. Deferiprone has been in use in Europe since 1999 but was not approved in the United States until 2011, due in part to a controversy over its safety [4 ]. 

A major theme in the 2012-2013 time period was comparisons of multidrug therapies against single-drug regimens. These are reviewed at the end of this section. An excellent review discusses the pros and cons of different iron chelation therapies together with associated side effects [1 ]. A major review comparing deferoxamine, deferiprone and deferasirox for the treatment of transfusion iron overload can also be foxmd [6 ]. 

Attempts have been made to reduce these side effects of hypertransfusion by continuous chelation therapy with desferrioxamine, but better products are needed. Animal experiments with 2,3-dihydroxybenzoic acid (2,3-DHB) are promising. Further studies of benzoic acid derivatives, hydroxamic acids and other compounds are in progress. The importance of reduction of iron absorption... 

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