A: With any parenteral drug dose the faster it is administered the higher the blood level will be and its effects are correspondingly stronger. CaEDTA has very low toxicity in most patients, but it is wise to consider the outliers in the population that can't tolerate a large drug dose that others have no problem with. In rats the LD50 of injected EDTA is about 1900 milligrams per kilogram weight of the rat (The Scientific Basis of EDTA Chelation Therapy by Bruce Halstead, M.D. (1979, Golden Quill Publishers, Colton, CA), so if we extrapolate that dose to an archetypical 70 kg human, the dose at which 50% of our patients would die is 133,000 mg, or 133 grams. Unlike rat researchers, it is imperative that we do no harm and so a total maximum dose of 3.0 grams has been accepted as safe by the chelation community based on many years of clinical experience. So while a rare patient may be harmed by the EDTA, it is more likely the toxic metals chelated by the EDTA are causing the liver damage. Dr Cranton quotes Halstead in reference to nephrotoxicity; "potential nephrotoxicity (hepatotoxicity? my addition) is directly related to the rate of administration and the dose of EDTA." (A Textbook on EDTA Chelation Therapy, 2nd Ed. Elmer Cranton, MD.2001.) We always maintain recent liver and kidney function test results for each patient in order to determine the safe dose for that patient. Even though the BUN and creatinine are normal and the estimated GFR is in a range that is considered suitable for i.v. EDTA, I consider the co-morbid conditions of the patient and their apparent health at the time of the i.v. It is my opinion that the ALT/AST increase in your patients is secondary to rate of administration and less so to the dose of EDTA. Just because a drug like CaEDTA can be administered comfortably over 5 minutes via a push does not mean it should be. I use CaEDTA only in a drip and administer it over one to one and one half hours; I have not seen adverse reactions during or after the i.v. or detrimental changes in liver or kidney parameters. Excuse the long reply, but I feel that this is an important matter that may deserve reconsideration (the 5 minute push) by doctors giving CaEDTA.
Regarding the slow decrease in liver enzymes - a reasonable treatment would be i.v. glutathione pushes 3 times weekly until test results normalize.
Dan Carter, ND