Students I have had have got over it.
One that worked with one - all are individual - was to break the lesson into 30 min slots, since he threw up about 45 mins in.
Then, as we talked, we realised it was due to blood sugar control - so, a little counter-intuitive, he ate BEFORE the flight to stop being sick!
Nice brown bread sandwich and a full sugar Coke.
Reckon, but am no doc, that the adrenaline rush of the start of the lesson burnt up the sugar (hence the Coke) and then the adrenaline during the flight burnt up the brown bread (ie slow release carbs)
Anyway, it has worked for him and I have found it has helped with a few others.
Main thing is getting the student to feel they are in control, that you are listening and that you have ideas that you are fully confident in (ie the placebo effect).