There are guidelines for treating children 4 years of age and older for ADHD, but no such guidelines exist for younger children. That lack of guidance hasn’t prevented the treatment of thousands of toddlers for ADHD.

Attention deficit hyperactivity disorder (ADHD) may be well known, but there is still a great deal that scientists don't know about it.

Clinical guidelines recommend treating preschool aged kids that have ADHD with behavioral therapy before trying medication. But few doctors may be following these guidelines.