Win50 The best and quickest herbicide for poison ivy I've used is Crossbow made by Dow. It turns black in 3 days after a dose. The product is not particularly toxic to people and is easy to spray on the plants. Does't have any onerous application requirements. and NO I don't work for Dow. Tried lots of other products. This is the best and it is not a restricted use herbicide. Anyone can buy it. Good luck.
PS In my extended family I'm the only one who isn't hyper sensitive to pi and I seem to be immune. 57 pi free years of crawling around turkey hunting, mushrooming, wood cutting, fence building and even some extra-curricular activity in the weeds.