M.M.
I haven't tried this, but someone I know swears by it. She told me she had an awful case of poison ivy and ended up in the E.R. where the doc on duty told her to run a bath as warm as she is comfortable with. Add a full carton of real old fashion oats....not instant. Soak in it until the water is completely cool. Towel off by patting, not rubbing. She said she did it that night and it was gone late the next afternoon. Best of luck!