I guess it could be but I've not heard of that reaction before - more sneezing, itchy skin reactions etc, and I guess the same could be said about the gammon
I really couldn't say either way
Has she had any of the other allergic symptoms?
Itchy, red, moist or scabbed skin
Increased scratching
Itchy, runny eyes
Itchy back or base of tail (most commonly flea allergy)
Itchy ears and ear infections
Sneezing
Vomiting
Diarrhea
Snoring caused by an inflamed throat
Paw chewing/swollen paws
Constant licking
(The piriton should work pretty quickly - has she been in the room with the new paint today?)