My son had his same issue. He has always taken a stimulant which helped, but when it wore off he was still very hyper and had difficulty sleeping. Our doctor recommended Intuniv with his regular stimulant and it has helped a lot. Also helped with with frustration he would get when his stimulant medicine would wear off.
So he now takes stimulant during the day and Intuniv at night. Also Intuniv is not fast acting and takes a few days to see the results. The first few days he started it made him super tired, but after about a week I started to see it help with his hyperactivity and the extreme drowsiness he had at first decreased.