The rash of poison ivy (we will use this as the prototype) is caused by exposure of the skin to the plant sap urushiol, and the subsequent allergic reaction. Like most allergies, this reaction requires previous exposure to the plant, and upon re-exposure your child will develop an allergic contact dermatitis. This reaction may occur anywhere from hours to days after exposure, but typically occurs one to three days after the sap has come into contact with your child’s skin and they may then develop the typical linear rash with vesicles and papules that are itchy, red and swollen. Poison ivy is most common in people ages four to 30.
During the spring and summer months I often see children who have a history of playing in the yard, down by a creek, exploring in the woods etc, who then develop a rash. I love the kids playing outside, but the rash of poison ivy may be extremely painful especially if it is on multiple surface areas, as in children who are in shorts and sleeveless clothes at this time of year. The typical fluid filled vesicles (blisters) of poison ivy will rupture (after scratching), ooze and will ultimately crust over and dry up, although this may take days to weeks. The fluid from the vesicles is NOT contagious and you cannot give the poison ivy to others once you have bathed and washed off the sap. You can get poison ivy from contact with your pet, toys, or your clothes etc. that came in contact with the sap, and have not have been washed off.
If you know your child has come into contact with poison ivy try to bath them immediately and wash vigorously with soap and water within 5