First of all contratulations!

My son was adhd as a child and has grown into a wonderful successful adult but he had to learn to journal to keep things straight in his hyperactive mind as a businessman, but especailly to finish high school and university.

When he was little I could tell if he had any sugar at all or anything with food dyes in it. Read labels because food dyes and sugar are in places we don't suspect them sometimes. You won't have any problems I'm sure. If he can't focus on things just remove as many distractions as possible so that he can concentrate on one task at a time.