Good advice from everyone so far. Just to clear up a misconception... The rash does not actually "spread". It may be up to 10 days before ALL the rash develops, but everywhere you get the rash, you have come in direct contact with the oil. The only way you can spread a poison ivy rash is to spread the oil -- by touching contaminated clothing, pets, smoke, ect. The fluid in the blisters is sterile and does NOT contain anything that can spread the rash. The danger of scratching is the chance of starting an infection. I know that doesn't help with your present situation, but maybe it can help the next time.