Myth: Poison ivy is contagious.
Truth: This is one rash that wont rub off on others. You react to poison ivy and its friends poison oak and sumac when the plants chemical urushiol (you-ROO-shee-all) gets on your skin, explains Dr. Parsons. Once the chemical is washed off your skin, you cant spread the rash by scratching it or scratching others. Since the rash often develops two to three days after exposure, the chemical is almost certainly washed off, she says. According to the American Academy of Dermatology (AAD), this delayed reaction can give the illusion that the rash is spreading when its not. To skirt an itchy situation, Dr. Parsons suggests immediately tossing clothes in the washing machine and washing exposed skin and possible contact areas with soap with some detergent.