Hi there and welcome!
If you navigate to the course section, or even just use the search function, you will find a TON of info on detoxing and healing the gut.
That being said, a three year old boy has no business being on medication for ADHD. It sounds like the school should be evaluated for not meeting his needs properly -if you can find a different daycare or keep him home, it would make a world of difference. 3 year olds -boys especially, are not going to “focus and stay on task.” but this is disruptive to a classroom and so they are punished, medicated and forced to sit down and be quiet. The system is broken and does not work for our kiddos -so we have to make it work for them. Montessori or Waldorf schools if available and accessible may be a better option, or even just a different place with more caring people (a nature school maybe) if you are not able to be home with him. You are your kids biggest advocate and first line of defense!