Wash thoroughly anytime you even think you may be exposed. I am very susceptible to it as well. I had heard years ago of a vaccine being developed at the University of Mississippi, I think it was. I have a cabin in the Trinity river bottom and poison ivy is everywhere. Good Luck.
I seem to remember that you’e NOT supposed to wash with cold water, or is it the other way around..and you have to use a strong soap, becuase otherwise you just spread the oils to more skin area....is this true?