| Hi Nate!
First the good news - you are most way through a normal course of poison ivy rash. Now the bad news - you are not through a normal course of poison ivy rash. The urushiol should be gone at this point and any spreading you see may be later breakouts (it can be hours to days before seeing a rash appear) or it may be that this is systemic. If this is systemic, expect to see the rash appear in odd spots for up to a few more weeks. Of course I have to say - I am not a doctor. BUT I have and many others on this board have suffered as you are doing now. There is hope.
For me, the most effective treatment has been to ignore it. I know this does not work for most as the itch can drive one absolutely insane (I'm probably insane anyway :-)). You might consider one of the many other treatments folks recommend to reducing / controlling the itch. Go to the treatments and cures section and try some of those. From what I know about Tecnu, it works best at removing the oil. The rash and itch are an allergic reaction and so that product is not going to help here.
My husband recommends the hot shower method that many discuss. Ice cubes many others have recommended but that is not long lasting. I have read several physicians recommending taking oral Benedryl (NOT the topical but the pill) which is an antihistamine to help control the bodies reaction (and consequently help control the itch). Commercial products such as Zanfel and Tec labs new IvyStat! help to control the itch by helping you to slough off a layer of skin (these are abrasive products).
I could probably go on and on but the issue is that everyone reacts differently. For some the commercial products work wonders yet for others they seek other remedies. Read up on what others recommend, see what makes sense for you and try a few. The most important thing you can do at this point is to make sure that the rash stays clean and dry. | 
