Contact with poisonous plants such as poison ivy, poison oak and poison sumac causes an allergic rash on between 10 million and 50 million Americans each year, according to the American Academy of Dermatology.
In fact, the AAD says these plants are the leading cause of allergic reactions in the United States.
“The reaction actually depends upon the person and what condition the skin is in,” said Judy Rasnake , director of Wellcare and Nurse Connection for Wellmont Health System. “As far as how often it occurs, it’s pretty common in this area — the ivy is.
“Of course, you’ve heard the saying, ‘Leaves of three, leave them be.’ Learn how to recognize it, and poison ivy is pretty hard to get rid of.”
According to the Food and Drug Administration, it’s actually the oil of the plants — called urushiol — that cause an adverse skin reaction. Even after the plants have dried out, Rasnake said they can still carry some oil.
Urushiol also stays on fabrics and even the fur of pets after they have come in contact with a poison ivy plant. Thus, a reaction may occur without ever touching one of the plants, but through contact with these fabrics or pets. A rash, however, cannot be spread from person to person, according to the AAD.
The best idea for preventing a skin reaction is staying away from these plants all together. The leaves of poison ivy and poison oak both appear in groups of three. Poison sumac primarily grows in boggy areas, especially in the Southeast, and has seven to 13 smooth-edged leaflets.
If you know you are going to be in an area where these plants may grow, Rasnake suggests wearing long pants and long sleeves and then washing any clothing after wear.
“The key is to wash everything because the oil can stay there (on the clothing) until it is exposed to the soap and water,” Rasnake said.
When contact with bare skin occurs, soap and water are still the best first course of action, Rasnake said.
“If you’ve been out and all the sudden you realize you’ve been in poison, the first thing you want to do is try to get to soap and water — and if soap and water is not available just water — and rinse the skin,” Rasnake said. “Usually, you can prevent a reaction if you can get that (oil) washed off within 15 minutes of the exposure.”
Redness and swelling may occur between 12 to 48 hours after exposure, the FDA said. A reaction typically runs its course in 14 to 20 days without any medical treatment.
During that time, itching can be reduced by using over-the-counter topical medications such as hydrocortisone cream or calamine lotion. Other options for relief of itching and swelling include oatmeal baths and cold compresses, Rasnake said.
Sometimes, however, a more severe reaction can occur.
“You have to be aware if you get it on your face or your mouth, your eyes or your genitals, and you start experiencing things like fever and headache and you notice there is pus in the blister ... you really should see a heath care provider,” Rasnake said. “At that point they may prescribe something for you, not only to help the symptoms, but to help get you through the initial infection.”
Severe reactions may also occur when the plant is burned and breathed in or through eating berries found on some of the plants. Rasnake suggests avoiding burning the plants, since the airborne particles may affect others in the immediate area. Breathing in the plants can cause a severe lung reaction in some cases.
For more information on poison ivy visit the American Academy of Dermatology’s Web site at www.aad.org and search for poison ivy.