I think many prescribers give ADHD adults a high dose too soon causing side-effects. In my experience, it's best to start with a low dose and slowly increase as necessary. The myth is ADHD responds quickly, but observing hundreds of patients it takes months, not days, for benefit of treatment to develop. There's wisdom in the phrase, "start low and go slow".
I have had bad reactions to every stimulant I tried since I developed bipolar 1 in my late teens (had taken them as a child for ADHD).
I had a good response to strattera, but there's a variety of them out there.