I believe Andy Cutler mentioned one mg per pound body weight as the maximum dosage for ALA or DMSA. Other sources mentioned a maximum daily dosage for DMSA as somewhere between 10 and 30 mg per kg body weight. At 10 mg/kg, it works out to around 0.57 mg per pound per dose, or 100 mg per dose for a 175 pound person.
Too much DMSA is rough on the kidneys and can case diarrhea.
I think I will limit my DMSA dosage to 100mg. Recently I have been using 66 mg as the DMSA dosage. ALA is much less toxic than DMSA. It is even available in 600 mg tablets or capsules. I think up to 200 mg per dose is a reasonable maximum dosage for a 175 pound person.