I know people are going to start booing me but I just have to share..
I had similar reactions to citrus and a poster by the name of prettysoulful shared her experiences with citric based fruits and mineral/calcium supplementation
which lead me to try calcium
it worked and worked well, no more red papules or itchy skin after citrus fruits. I know now that I had a deficiency because of a lot of other health symptoms cleared up too. Dont forget Vit D, its extremely important in assisting with Calcium absorption, I was low on that too (showed up on blood test).