My 26 year old son has a rare form of Down syndrome called mosaic Down syndrome. He was dx with ADD when he was 9 or 10. We tried Ritalin, Strattera and eventually Concerta. When he was younger, he had drug holidays during the summer. He graduated from HS with a diploma and got 6 welding certificates in college. He is working full time in a welding shop as a Shop assistant and welder. He ran out of his script a few days ago and seems more upbeat and less anxious. We are reluctant to consider a trial without the Concerta because of the impact on his job performance. What do you recommend?