Poison ivy, poison oak, and poison sumac commonly cause skin rashes in children during the spring, summer, and fall seasons. An allergic reaction to the oil in these plants produces the rash. The rash occurs from several hours to three days after contact with the plant and begins in the form of blisters, accompanied by severe itching.
Contrary to popular belief, it is not the fluid in the blisters that causes the rash to spread. This spreading occurs when small amounts of oil remain under the child’s fingernails, on her clothing, or on a pet’s hair that then comes in contact with other parts of her body. The rash will not be spread to another person unless the oil that remains also comes in contact with that person’s skin.
Poison ivy grows as a three- leafed green weed with a red stem at the center. It grows in vinelike form in all parts of the country except the Southwest. Poison sumac is a shrub, not a vine, and has seven to thirteen leaves arranged in pairs along a central stem. Not nearly as abundant as poison ivy, it grows primarily in the swampy areas of the Mississippi River region. Poison oak grows as a shrub, and it is seen primarily on the West Coast. All three plants produce similar skin reactions. These skin reactions are forms of contact dermatitis.
Treating reactions to poison ivy—the most frequent of these forms of contact dermatitis—is a straightforward matter.
Prevention is the best approach. Know what the plant looks like and teach your children to avoid it.
If there is contact, wash all clothes and shoes in soap and water. Also, wash the area of the skin that was exposed with soap and water for at least ten minutes after the plant or the oil has been touched.
If the eruption is mild, apply calamine lotion three or four times a day to cut down on the itching. Avoid those preparations containing anesthetics or antihistamines, as often they can cause allergic eruptions themselves.
Apply topical 1 percent hydrocortisone cream to decrease the inflammation.
If the rash is severe, on the face, or on extensive parts of the body, the pediatrician may need to place your child on oral steroids. These will need to be given for about six to ten days, often with the dose tapering in a specific schedule determined by your pediatrician. This treatment should be reserved for the most severe cases.
Call the pediatrician if you notice any of the following:
Severe eruption not responsive to the previously described home methods
Any evidence of infection, such as blisters, redness, or oozing
Any new eruption or rash
Severe poison ivy on the face