"Is there a cutler's protocol that covers dmps suppositories? Our DAN doc wants to do 2 suppositories twice a week, but Ive read that that can be too much for the body for a 3 yo"
Cutler's protocol is for oral chelators ONLY. In his protocol chelators must be dosed at specific intervals (4 h or less for DMSA, 3 h or less for ALA, 8 h or less for DMPS) for a period of several days - to keep blood levels of the drug fairly constant and to allow for removal of metals during the chelation days - and then as many days off of chelation as days on to allow the body to rest. There are also certain supplements that are essential to chelation with Andy's protocol. For details see his two books at http://www.noamalgam.com
There are several things wrong with chelation with DMSP suppositories. Suppositories are not a suitable delivery system for chelators because absorption is erratic and sticking something in ones rectum every 8 h or so would be very uncomfortable and unreasonable to expect anyone to tolerate - it borders on child abuse to do something like that to children. The dose in the suppository would be too high and a high single dose of DMPS would lead to significant redistribution with little excretion. The redistribution will lead to worsening of symptoms and it will be more difficult to chelate properly later on.
For support with proper chelation of children join the autism mercury yahoo group. Andy often visits that group and answers questions.