To cure poison oak or poison ivy, wash the area with soap and water right away, then rinse, and repeat three times. This will remove most if not all of the poison. The same treatment can also be done with rubbing alcohol. Where soap or alcohol is not
available, rinsing over and over will at least get rid of some of the poison.
From Back Fence Wisdom: An old Indian remedy for the itchy rash caused by poisonous plants such as poison ivy, poison sumac, and poison oak requires a paste made of the crushed leaves and stems of the Jewelweed plant. Also known as "touch-me-not," you might find this relative of the impatiens growing near the offending poison ivy plant. Wash the infected area as quickly as you can with cool, clean water. And apply the paste. You can also take Jewelweed Anti-Itch Spray into the woods with you. Boost your healing system by drinking lots of milk and eating fruits high in vitamin C.
When the rash appears, you can get immediate relief from rubbing it with the rind of a watermelon, lemons, a banana skin, or oranges.
If itching continues, you can use a paste of water and either Baking Soda or Cornstarch Powder.
If you are in the habit of relieving yourself in the woods and using a leaf as toilet paper, it really is a good idea to know which leaf is which! (Don't laugh, this has really happened to people.)