Thanks, everyone for the insights and information.
DS has been on Tenex for 4 weeks. We have seen a positive affect on his ability to pay attention and stick with tasks. He is completely his homework more quickly and with more accuracy and he is getting better reports from school. Additionally, his language skills have improved (longer, more coherent sentences) and he seems more socially aware. I'm not sure if these improvements are due to the medication, or are just part of his natural development, since he tends to have leaps and plateaus in both these areas (and he was due for another leap). Either way, we are happy that the medication seems to be helping him. So for now we are going to continue with it and see how things go.
Gena
DS, age 11 and always amazing
“Autistics are the ultimate square pegs, and the problem with pounding a square peg into a round hole is not that the hammering is hard work. It's that you're destroying the peg." - Paul Collins, Not Even Wrong