Boyfriend is year 2 med student, can't focus

Year 2, studying for his first board exam. He took one day off for my birthday a week ago. (He does have ADHD). One day off of studying turned into 2, but as we'd gone out Friday night it seemed appropriate. It's now been 6 days, he can't just sit and start. He's got anxiety over doing it and even if he goes into the office he ends up coming out complaining of dry eye or anxiety 30 mins - an hour later.

I'm trying to be a supportive spouse in this situation. But it does seem like the more i say 'please go study' the more he wont. Has anyone else had experience with this? He definitely goes through periods of complete burnout but board exam is less than a month away and this is the least I've ever seen him do. Anyone have any advice? I've also tried being gone all day, hoping it'd give him one less distraction, maybe it'd help, to no avail.