Hopefully your not still itching but if so I'll see if I can help.  I've seen several cases and some worse than other depending on many cases.  I have 3 children and 2 out of 3 get into it every spring.  They love to spend time building in the wooded acre and well you know the rest of the story. 

This is what I do.  There's a product called Rabbott's poison ivy/oak/sumac remedy which can be found on www.physician.com.  Just look under Rabbott's Remedies for it.  As soon as anyone notes the itching begin, I swab the area that's itching with this formula.  Usually withing a few days or less, there is not remnants.  However, in severe cases I've added blood cleansing teas to there diet and or tinctures.  Burdock and chickweed are a few teas that certainly comes to mind.   Good luck