Do you mean a flare that instantly happens ?? when you are out & about,vs one that is already happening and you go out & about - it gets worse???

I only had slight nausea during the dizziness times early on. I guess I did have the dizziness almost to point of a faint a few times.
But I just stood still and took calming breaths till it passed.

But I think for me those feelings were due to the vertebral artery being messed up by spasms and pulling the on the vertebra themselves.
It faded away after being off work & good PT.