The beginning of summer kicks off the camping and hiking season, anxiously awaited by those who have endured a long cold winter. This year will likely prove to be one of the busier camping seasons as many Americans bypass more expensive vacations that involve pricey airline tickets or gas guzzling road trips. Emergency department staff will probably see a greater number of people with contact dermatitis caused by exposure to poison ivy, poison oak or poison sumac.
Many people have never seen poison ivy, or perhaps wouldn't recognize it if they saw it. Poison ivy, poison oak and poison sumac belong to the plant genus Toxicodendron (previously referred to as Rhus). Toxicodendron means "poisonous tree." These plants have an oil-based substance in the resin on their leaves and in their stems and branches called urushiol that causes a delayed skin reaction in about 50% of people that contact it. Urushiol may cause severe contact dermatitis in people that have previously been sensitized to it.
Urushiol causes a delayed type of immune reaction which may take hours or days to develop. Sensitization takes place after first contact with urushiol. Sometimes the skin rash takes more than a week to develop after initial skin exposure. The next time there is contact with poison ivy, the reaction is more rapid and often more severe. Within hours or by the next day, itching, burning, and blistering may be present.
What can I do to avoid getting poison ivy dermatitis?
1) Familiarize yourself with the appearance of poison ivy, poison oak and poison sumac (click on the link to see illustrations). Poison ivy is widespread throughout the United States. Poison ivy and poison oak usually have three leaflets joined by a stem (Remember the old rhyme: Leaves of Three, Leave Them Be! ). Sometimes there are more than three leaflets. Poison sumac may have 5 or more leaflets. Poison sumac is not as widespread as poison ivy. It is mainly found in very humid, uninhabited areas in the southeastern part of the U.S.
