compeed blister plasters

Has anyone used these recently and had a reaction to them?

I've never had any problems with them, until I bought a new pack
within about 20 minutes of putting them my skin under and around them became itchy and felt like it was burning

i left them for a while, thinking that maybe it was just coincidence, but ended up having to take them off because of the pain
this was on sunday, and now my skin where they were is very painful, itchy, and covered in scaly flaking skin
like a chemical burn

i'm not normally allergic to plasters, although I do have quite sensitive skin, and was wondering if anyone else had had any problems that might suggest they'd changed the ingredients recently