Originally Posted by mattoak
But I think you can become sensitized and develop an allergy so the more you expose yourself the greater chance there is of developing the allergy.
I have heard this to be true as well but I have gotten deep into PI several times and, despite my paranoid itching, never developed a reaction. A friend of mine used to be a landscaper who wasn't allergic so he always got sent in to remove the PI and he still doesn't react to it.
I still try to avoid it just in case I do ever develop a reaction, you never know.