First, stop seeing the arpn. I had 2 that wanted to lower my son’s dosage because they thought it was too high. The other part of this was they had no idea he has been under care of a psychiatrist for 5 1/2 years now (yes, my ex husband doesn’t want him medicated). I stopped it right there and went to the Dr at the practice. She understands the cost/benefit of it and would not suggest that. Most physician offices do not know about the various levels along with the comorbid conditions of ADHD.
Find a doctor who is willing to work with you. You know what works and I wouldn’t change mine either, I have been told the same thing about how much Ritalin I take. I’ve been through the rounds of testing and the other part is I cannot afford the copay of a non generic prescription.
Best wishes to you.