When you stop a stimulant for an extended period, you need to start back at the lowest dose and titrate again. That jump from 0 to 15 could be causing some of the irritability and mood issues. Or, he just may not be able to tolerate that medication anymore.
There are two types of stimulants: amphetamine (Adderall, Vyvanse, Evekeo…) and methylphenidate (Ritalin, Concerta, Quillivant…). Almost everyone does well on one type or the other, but not both. So, if he’s done well on Adderall in the past, that could signal that he does best on amphetamine based stimulants. The only way to know which is best for him though, is to try both types. So, maybe it is time to try something like Concerta.
Discuss all of this with his prescribing doctor.
ADDitude Community Moderator, Parenting ADHD Coach, Podcaster & Author, Mom to teen w/ ADHD, LDs, and autism