|Use hot water treatment at your own risk. No one here that recommends it stops to think about what else it does. It makes your skin absorb the urushiol deeper into the skin by forcing open the pores and increasing blood flow. This is a scientific fact. But hey, some people never listen no matter what.
The methods you are already using are very good for itch relief and safe. Two hours of relief is darn good. Some people swear by Technu or Zanfel scrubs. Even if you pop for a steroid topical ointment, I think you are going to be disappointed...you'll see that most of them do nothing really for itching. I tried prescription as well as over the counter creams years ago with my first ever case of PI and they did nothing except make my rash feel smothered and hotter--and that made it itch even more. Cold cloths and ice cubes have always worked best for me and medical professionals concur. The ICE analgesic product is a winner too. Get well soon! firstname.lastname@example.org