I think that Poison Ivy dermatitis--which is unknown in Europe--is an
allergic reaction: no one gets it on the first exposure.
I am not a believer in holistic medicine, but an excellent folk remedy that
works far better than any commercial topical preparation is a tea made from
Sweet Fern, Comptonia peregrina, which is not a fern but a shrub that grows
in the Pocono Mountains and other cool climates around here.
John Wolff
2640 Breezewood Dr.
Lancaster, PA 17601, U.S.A.