cortisone.

Ice packs!

Bleach? EEK.

Oatmeal baths: Aveno is Ok, but the real deal works just as well. Big ass handful under running water.

+ Good ole calamine.

baking soda in your bath water sometimes helps, too, from what I remember.

Make sure you're diluting that bleach good.

Cut it off. It's the only way to be sure.

you don't by chance have any heroin around, do you?

I have had poison ivy more often than not in my life. Quelling the itch can take a lot of willpower; there are a few things that help. Ice will soothe it, but you have to keep the ice on. As soon as you remove ice, it will itch like the devil. That's why I recommend running hot water (not searing hot, but hot-shower hot) over the affected area for a few minutes. The hot water will, while it's running, make the rash itch like crazy, and if you have sores, they may suppurate and run a bit. But as soon as you dry it off, the air feels cool, and you won't feel any itching at all for a half hour or so, and if you can ignore it for a half hour, you can usually conquer it for a bit longer because you're used to ignoring it by then.

They've got some new sprays and stuff that are supposed to soothe, but ymmv with them. I find that drying lotions make the rash last a few days longer.

But really, hot water's the best thing, because when it stops working you can always do it again.

Also, if you think you still have the sap on you (if you've had it for just a day or so) I recommend washing the area repeatedly with Boraxo, that powdered mule train soap. It's a little gritty so it might feel like you're scatching, but it's been getting urushiol off my skin since I was a lad.

Good luck, and remember: the itch is in your head. Think about something else. If sitting around thinking doesn't distract you, find something else to do.

When I have bug bites (I get THE WORST mosquito bites), I usually cover it up with cloth or medical gauze or something. This helps me both ignore the itching (it's easier if you can't see it) and also protect from scratching (which can irritate the skin and spread the infection). I reccommend long sleeves, thin enough to breath but thick enough to damp out the effect of scratching.

Calamine at first and cortisone after. Aloe balms and moisturizers can help if there is drying and cracking. Aloe is very good at promoting healing of burns and damaged skin. Better than just about anything that Big Pharma has cooked up. It's still one of the few effective treatments for X-ray burns.

Hugh is right about getting the waxy oil that carries the irritant off. Sooner is better. That shit sticks to you.

Alternating ice and warm / hot water will promote blood circulation and speed healing. If the erruption is really bad, wait for healing to start, because vascularization will also promote the formation of scar tissue. Ice alone does not cause vascularization or promote scarring.

Bleach is going to injure tissue, since it is drying and somewhat corrosive alkaline. It will, however, kill off any anthrax or ebola that you come into contact with. Any alkaline soap (Boraxo, Lava) with abrasives will get that crap off your skin, but you have to get it early to get a real benfit. So yer Grandma sort of had the right idea, but the removal of the irritant is what is probably going on. If you want to continue to use bleach, do it early and do it only once.

I learned this the hard way clearing land on a building site in the Santa Cruz mountains. It was poison oak, but the irritant is the same.

Make sure you wash carefully, wash the clothes you were wearing in hot soapy water. Also wash anything you touched, any pets, etc etc. Once the actual oil is gone you should start healing fairly quickly.

I've been advised against calamine by my friend who gets poison ivy really bad. He says that the sores won't heal under a layer of calamine, they'll just stop itching temporarily.

treatment in Wiki

also

I got poison ivy for the first time in my life last summer. I'd always been immune, so I never watched out for it. I got it from my chin to my hip all down the left side of my body. I was in agony. The absolute only thing that helped was hot water. Specifically, holding the affected area under the hottest water I could for as long as I could. It was surprisingly effective at stopping the itch.

Also helpful: swimming as much as I could. Chlorine (or salt water) + sun. Dried it up pretty quick for as bad as it was.

Hope you're feeling better soon. Poison ivy is awful.

By the way, I get that shit in NYC, in the winter. I mean, what the fuck? What the fucking fuck, god?