How does everyone here keep track of mystery reactions like this, if at all?
When we go through times with random hives, which really happened moreso when the boys were younger, we just kept track on a piece of paper. We wrote down everything they ate, kept track of what we were doing... or if we went somewhere.
Paired with that though was to sort of reduce the actual things we ate, and make sure they were easy foods that we knew were safe, or were just one ingredient. So, no eating foods prepared outside of the house, and be super simple .... like rice with chicken.
Also, we cut back on what we did or where we went. Sticking to short outings. Lots of wipes.
It really all depended on how often it was happening. We sort of lived in a way where sometimes it is like doing an elimination diet with your diet and your activities, and treating everything you touch as though you need to decontaminate after touching it. Sometimes you are able to figure out what it is..... sometimes not.... as you slowly add foods back in or activities.