So the doctor prescribed a series of 200 shots of "rhus tox" anti-allergy serum, a decoction of Poison Ivy venom that would gradually desensitize me to its effects. Every day at the school break, I would walk the 4 blocks to the doctor's office and get my shot, till I'd had all 200.
It worked. I can still get it (I have a little patch on my hand now from clearing an old cemetery on our place), but it's not bad and not dangerous.
The other positive by-product is that I don't care anything about getting a shot ever since then. Go ahead, shoot me up, I don't care - AH'VE 'AD WORSE!
Still gonna wait until my doctor calls me in on this one, though; no random bugger in a parking lot is sticking ME with something that CNN told me to get!