Often it's SLS in the product, it's a foaming agent. It started 4 me a few years back: sugars in particular react: bananas, sugar on fruit, sugar in tea 
What a nightmare it must be for you! On another note my symtoms are coming thick and fast! Ive had hot flushes in past but come and go after a few mins. For past couple of days I am getting an intense heat on my chest up to right side of neck and ear. It's a burning internal heat! I am on Sandrena gel 0.5mg a night day 13 on it. If you were in my shoes would you continue as is for 3 months or ring Gp to consider increasing? I am burning up as we speak!
