This reply was originally posted by user adhdmomma in ADDitude’s now-retired community.
I would sit down and write up a contract with him—what you expect from him and what he can expect from you. You can stipulate that he must get ADHD treatment in order to remain at home. And maybe a job or enrollment in school. And he can expect from you a roof over his head, support and help with his ADHD, treating him like an independent young adult, etc. This will show him that you’re on his side, but that he will have to do what is necessary to be a pleasant part of the household/family.
Here’s a great article on this as well:
ADDconnect Moderator, Author & Mentor on Parenting ADHD, Mom to teen w/ ADHD, LDs, and autism