Yeah, I also wonder SL, she has some history of cancelling appearances. One was in Boston this winter. Weather was balmed, but every other act on the same tour made it here, no problems. They were all in NYC the night before.
I'm thinking her "reaction" is likely of the overdose kind. She is heading for an implosion. She apparently has been self-medicating to deal with depression, going non-stop, and recently had a flu which she may not have completely recovered from. It's the antibiotic for the flu being blamed for the allergic reaction.
And remember, two years ago she went gluten free because of a a gluten and lactose allergy. She tweeted: “The change in your skin, phyisical and mental health is amazing! U won't go back!”
I don't immediately assume it's an allergic reaction just because she says it is.
While eliminating an allergen can have positive effects on your skin, physical and mental health...would you follow that with "U won't go back!" ?