The higher my son’s dose of stimulant, the more aware of pain he became and then he hyperfocused on it. Without medication, he could get minor cuts, scrapes or bruises and never realize it.
Stomach aches are common with these medications, especially those that are time-release. I don’t know that reflux is though.
Another possibility is anxiety. It can cause significant physical effects.
ADDitude Community Moderator, Parenting ADHD Trainer & Author, Mom to teen w/ ADHD, LDs, and autism