The reason most people have a bad reaction with chelation is because they first dont use either artichoke to clean the liver for 1 month, and then use milk thistle and horsetail for liver/kidney/lymph support.
Start with your chelation 1/4 the recommended dose (includes IV chelation) and wait 3 days and see how you feel. Adjust according to how you feel. If your a highly toxic person doing a full dose could cause serious lifelong problems from detoxing too fast. Look at taking 6 - 12 months to do your detox, not a couple weeks. It takes time, but does work, go slowly, drink clean water and take antioxidents like pcnogenol. Use lots of Sea Salt s on your food to remineralize 5 hours after chelation. Use a 1-1 calcium/magnesium product from Genestra is good. Take cilantro with and 2 hours after your chelation with DMSA. I wouldnt worry about alpha lipoic acid. If your stirring up the metals slowly should be fine, and the cilantro will take it out of your blood stream. Use a Bentonite clay / apple pectin fiber 2X a day. If contipated also use sprouted flax. If its real bad may have to take some senna for a few weeks until its moving.