Sounds like it might be systemic if it continues to be spreading this late. Good idea to see the doctor.

Stay calm. It will eventually go away. If the itching is driving you crazy you can try one of the itching remedies provided by others. I use zanfel myself but make sure it really is a poison ivy rash since zanfel doesn't work on other types of rashes like some of the other more general commerical products which are solvent based, much more reasonably priced... and handle most toxic oils. See how soap works page for more information on why.

I only use Zanfel when I have those "I can't take the itch, can't sleep type of rashes" because of the expense. My wife has no problem using mind over matter. I have never heard of steroid oil but I am not up on medical stuff as it all scares me. I am of the do it yourself with soap, other household items and put dirt on it kind of mentality. Not terribly enlightened!