
Poison ivy, poison oak, and poison sumac, all members of the plant genus Toxicodendron, are the three most common plants that cause contact dermatitis in America. Captain John Smith was the first to report an allergic disease in America related to these plants. Approximately 85 percent of the population will develop an allergic reaction to poison ivy, oak, or sumac if exposed to them. Treatment includes prevention by wearing long sleave shirts and pants, using skin protectant creams such as Poison Ivy Block before being exposed to the plants. Washing with a strong soap or Technu which washes off the resins of the plants after exposure to the plants can be helpful.. Hyrocortisone 1%, Sarnol HC or Aloe Cort Cream in addition to over-the-counter oral benedryl can also relieve the itch.