I am assuming he already had a sleep study but just in case he hasn’t you might want to consider offering him that. A lot of people with adhd have sleep disorders also which make the adhd symptoms worse. Some people have a REM disorder (or something like that) which they take medicine for and it helps with more refreshing sleep. There are a bunch of sleep issues you can have which I had never even heard of until my son and I went to see a sleep doctor.
I have ADHD /depression and mild sleep apnea and it is soooo hard for me to get going in the mornings. My 17 yo son has missed so much school this year for a myriad of reasons. One of those is his difficulty getting up in am and he actually said to me one day “at least you get up and go to a job that gives you a paycheck- what do I get by going to school?” And he knows the answer is he gets to go to college which then gets him the job he wants to have and the lifestyle he wants. The problem is that is so many years away that for a teen brain, let alone one with ADHD, is not going to get much of a dopamine “hit” (motivation) from that alone. As you know to those of with ADHD time looks like this to us: Now and Now – that’s about it.
The other thing you may want to look into, if you haven’t already, is how much of his lack of motivation is not only ADHD related but the depression part. That requires different medications-if he is willing to do that. Addressing my son’s depression in addition to adhd meds has helped a little bit I will say.
And also I was just reading about MTHFR and its effects on serotonin/dopamine. My husband and I each did the 23 and me gene testing and both have the variant for MTHFR. I watched a you tube video today about it – fascinating. I’m going to talk to his pediatrician next week. You might want to just google that and see if you can relate to any of those symptoms.