ALA is the way to go, I am now of the opinion that most of the headaches and brain issues are caused by the pollutants (Tellurium, Thallium and Cadmium) as well as Copper and Zinc. Perhaps that is why RLA worked for me.
Certainly now that I am using Homeopathic mixes for these there are no further issues, also I am able to keep my ALA much lower which in my case is important since ALA still stirs up way to much Hg.
Taking 250mg of ALA will throw me back to memories of pre DMSA and make my Thymus pound like it wants to leave my body.
IMO, best to increase DMSA slowly to your max dosage of 1mg per pound of body weight every 3-4 hours then add the ALA and stay at ~12.5mg for a long, long time before forcing it higher.