The feeling that something is crawling on you can be a side effect of meds. I’m surprised that he’s having it on both an amphetamine and a methlyphenidate. My son actually had it with Intuniv, not with stimulants. All you can do is keep trying different meds. It sounds like things were best controlled on Vyvanse, which is an amphetamine. So you might try a different amphetamine — there at at least 4 on the market now I think.
ADDitude Community Moderator, Parenting ADHD Trainer & Author, Mom to teen w/ ADHD, LDs, and autism