Hi Bex. I know that stopping the mercury exposure doesn't cure right away your problem. This has been discussed before , and this is with a much higher probability because of the pathogens your body has accumulated during the exposure, than the stored mercury itself. It would be incredible if the pathogens also vanished in a short time.

It also explains why some people need to be exposed to much smaller amounts of mercury than others, to achieve the same rock bottom health. Some people just have an immune system that can tolerate better a greater mercury load without compromising their immune system activity.

The exposure to mercury and lead is much more harmful to children than to adults, because the nervous system is still developing, and an interference in that process is very harmful. The organic mercury used in vaccines is, however, much different (and more dangerous) from elemental mercury used in fillings. Some species of organic mercury stays in the bloodstream much longer than elemental mercury after exposure. Thimerosal contains ethyl mercury, but it's half-life in bloodstream is short, but it may accumulate in brains. There has indeed been demonstrated some trouble with the APOE-genes that transport mercury out of brain in autistic children.
But DMSA doesn't chelate deep organ mercury, so why would it help autistic children if mercury accumulated in the brains? Wouldn't ALA be the preferred agent in this case?

Regarding the bad symptoms from DMSA: I have gotten bad reactions from nearly everything, and that is not a proof tha t mercury is chelated.