Better to use Tecnu's barrier cream. In fact, I was actually able to find some of the cream here in the Midwest. Now I just have to hope that the stuff works. The Tecnu cream presents me with another minor problem. I also need to wear sunblock.
Regular soap is fine.
The Tecnu cream presents me with another minor problem. I also need to wear sunblock. You want the Tecnu on the outside. OK to apply more sunblock later, tho. Urushiol is one of nature's most potent skin irritants.