By Ginna Parsons
TUPELO – Summer is finally here and with the season comes an unwanted guest: poison ivy.
Poison ivy tops the list of plants to avoid because it contains urushiol, an oily resin that binds to the skin on contact and causes an itchy rash with burning skin blisters.
“There exists both poison oak and poison ivy, but poison ivy is what’s most common in this part of the U.S.,” said John Byrd, professor of weed science at Mississippi State University in Starkville. “We don’t often see poison oak in Mississippi.”
The best way to avoid poison ivy is to know what it looks like.
“The old saying, ‘Leaves of three, let it be,’ does apply to poison ivy,” Byrd said. “There are three leaflets and more often than not they are smooth-edged. The most common plant that poison ivy is confused with is Virginia creeper, but it’s a palmate – it has five leaves.”
When poison ivy first appears, it looks like a tiny shrub, Byrd said, but if left undisturbed, it will grow into a vine. Berries typically appear in mid-summer or later that look like a small cluster of whitish-green grapes.
“I do know from personal experience working in flower beds around the home landscape that the underground plant parts – the roots and rhizomes – have a higher concentration of urushiol than the foliage itself,” he said.
“And when the weather turns desirable and people are weeding flower beds, it can be quite easy to expose yourself to the roots and have a more severe reaction than in the summer months,” he said. “The plant loses foliage in the fall and it’s more difficult to identify.”
People also have a tendency to burn debris they dig out of flower beds, which can be problematic if poison ivy is in the mix.
“Urushiol does move in smoke and it can cause infections in the eyes and the lungs,” he said. “Burning is not always a smart move to make.”
Before you start weeding a flower bed, you need to be properly attired, Byrd said. Wear long sleeves, long pants, long socks and elbow-length rubber gloves. Cover any exposed area you can.
“If I had poison ivy in a flower bed, I’d remove it by hand,” Byrd said. “Herbicides like Roundup are very effective, but you have to be careful to avoid drifts to desirable plants. If it’s growing up a tree, cut the vine and then apply Roundup to the part in the soil with a paint brush. That will kill the plant entirely.”
But what happens if you’re careful and you still get the plant’s oil on your skin?
“If you are exposed to poison ivy, try to wash the oils off within 5 minutes and you can help prevent breaking out,” said Dr. Jeff Houin, a Tupelo dermatologist.
When you take your clothing off, don’t let the side that was exposed to the oils touch your skin.
“In other words, don’t turn your shirt inside out and pull it over your head,” he said.
And don’t think your four-footed friends are immune to the poisonous plant.
“Pets can carry the oil on their fur,” Byrd said. “Put on rubber gloves and shampoo them.”
If you do get the oil on your skin, you can expect a reaction in 24 to 48 hours, Houin said.
“It will be a red area with small blisters in a line where the plant has touched you,” he said. “Contrary to popular belief, you can’t spread poison ivy by scratching. The oil is such a strong allergen that the immune system remembers it. You can break out in any place you’ve ever broken out previously. For instance, say you got it two years ago on your leg and now you get it on your arm. You can break out on your leg as well.”
Some people think they’re not allergic to poison ivy and maybe they’re not – today.
“But if you touch poison ivy enough, you will become allergic to it,” Houin said.
“Your tolerance can change at any point in time,” Byrd said. “In grammar school, I wasn’t allergic but now I am allergic to it. It’s the same with bee stings or anything else. Your system changes over time.”
The blisters can last anywhere from three to four weeks, Houin said.
“It does need to be treated,” he said. “It’s not contagious, it’s not going to spread, but it is uncomfortable.”
If the rash is in a small area, a topical steroid cream or gel is fine, he said. If it’s spread over a large area of the body, an oral or injectable steroid is preferred.
Bill Austin, a pharmacist at Walgreens, said over-the-counter 1 percent hydrocortisone cream will take down the inflammation and itch of poison ivy.
“And you don’t have to dry it up, but people think you need to, so for that we recommend Caladryl Clear,” he said. “It has calamine in it plus Benadryl, an antihistamine, so it dries up the blisters and helps with the itching.”
Austin doesn’t recommend using the hydrocortisone cream more than four times a day, so supplementing with Caladryl Clear in between can bring some relief.
An oatmeal bath can also help dry up blisters, Houin said.
There are some preventative creams out there, such as Ivy Block, that claim to be a barrier between the skin and the oil and are intended to be used before you come in contact with the plant, Austin said.
“I don’t know how effective it is,” Austin said. “If you’re truly allergic, I don’t know if it will keep you from getting poison ivy. But if you have a mild allergy and come in contact with the plant, it probably works OK.”
There is a product on the market called Tecnu that you can use after exposure to poison ivy when you can’t get to running water to wash the oils off, Austin said.
“You rub that on it and it helps get rid of the oil,” he said.
This would be a good product if you were hiking or camping or in a situation where you couldn’t get to water quickly.
“But when you get to where you can shower, you need to,” Austin said.
Byrd said if you know you’re highly allergic to the vine and you have a lot of it in your yard or garden, you may not be able to handle it safely without having a bad reaction.
“You might need to seek outside help,” he said. “But again, you have to be able to identify poison ivy. If there are leaves of three, let it be.”