Hi! My son is 6, dx at 4 with ADHD and ODD (oppositional defiant). We used guanfacine starting at age four and still do, along with a stimulant. My son is defiant and oppositional, as well as hyperactive and impulsive but has no symptoms of inattention. We have been quite happy with guanfacine; it helps a lot as a “bridger” for when stimulant wears off after school. It also helps with emotional regulation. I saw a youtube video of Dr.Russell A. Barkley talking about guanfacine and how it helps with emotions etc, so that might be worth looking into. We dose our guanfacine in an unusual way, just solely based on trial and error of what worked best and we have been at 1/4 of a pill in the morning with the stimulant and then the remaining 3/4 at 4:30pm, using that dosage schedule for over a year now. I find that it helps my son to sleep at night (without it the stimulant keeps him up, even though he takes it only once early in the morning). His behavior is far from perfect with just guanfacine in the evening, but he is not bouncing off the walls, completely out of control like he would be without it. I have to rely on a lot of behavior modification in the evenings to get us through. I hope that helps. Best wishes, thinking of you.