DMSA can be started 4 days after removal, no ALA and check your supplements for that as well. The organic form of Hg will travel to the brain faster with ALA in your system. There it will bind to other minerals making it far more difficult to remove.
Cutler gives a simplified description: Rate of mercury from brain is proportional to the concentration of ALA in the brain times the amount of free unbound mercury in the brain. Rate of mercury to the brain is proportional to the concentration of ALA in the body times the amount of free unbound mercury in the body. Together these dictate the net movement of mercury between the body and the brain, but at any moment in time, there is mercury moving both ways. http://onibasu.com/archives/am/81363.html