|I'm sure that for every plant, food anything alive & medicine... there is a person who is allergic to it. I'm allergic to wild columbine & it acts just like poison ivy rash, with oozing etc. so I treat it the same way & it's much easier to avoid. My dermatologist says many people are allergic to the sap of Chrysanthemums & get a horrible rash etc. from it. So take care you don't get sap on you when you cut any flower or plant, except maybe the aloe.
Watch what you put on the rashes & blister. DON"T put bleach or gasoline on them I don;t care how it helped your grandpa.. it can burn your skin worse & cause infection. and whoever was considering burning it off has got to be out of his gourd. Use lots of cool to tepid water to remove when 1st washing, to try to remove the oil... hot water will open pores & help it get in. Save the hot water for days later when trying to get rid of the itching if you get the rash.
Remember that poison ivy et al is spread by it's oils so wash it off with LOTS of water within an hour of contact..the present thinking is that soap may help spread it. Or use alcohol & then wash that off with water. All clothes, shoes ,pets have to be washed ASAP. If you use TECHNU that has to be washed away too including if you rubbed it on a dogs fur, wash it off with water. The oils will last for Years on anything it touches if not removed.
REmember also that you do not 'catch' poison ivy from someone else's oozing only from the urushiol oils itself...the only way to catch it from another person is if he still has the oils on himself or clothing or gloves or tools, rakes or pet...every thing has to be washed off with lots of running water & watch where it runs off to.