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Beware of Poison Ivy, Poison Oak, and Poison Sumac!

Published on May 16, 2011 with 4 comments

For those who love to be outdoors in the warm spring weather, be aware that poison ivy, poison oak, and poison sumac are growing everywhere.

For those unfortunate individuals who are allergic to these plants, even the slightest contact to urushiol, the oil present on the leaves of poison ivy, poison oak, and poison sumac, will likely cause a red, raised, and extremely itchy rash called allergic contact dermatitis. Almost immediately upon contact with the skin (within 5-30 minutes), the urushiol oil penetrates the outer layer of skin. Once it has progressed to the deeper skin, the inflammatory process will begin. In most cases, the poison ivy rash (and likewise, the poison oak rash and sumac rash) usually appears 8 to 48 hours after exposure but can be delayed by up to 14 days! While still on the surface of the skin, the oil can be spread from the area of direct contact to other areas of the body. However, once the rash appears, it is not contagious to oneself or to others, even if fluid is oozing from the blisters.

The poison Ivy rash can be quite mild and localized, but severe cases can occur. The poison ivy rash will typically present as red, raised streaks on the arms or other areas of contact, and will often blister. Systemic involvement can be quite severe and result in widespread rash, eyes swollen closed, facial swelling, genital swelling, intense generalized itching, and overall discomfort.

One should learn to identify these poisonous plants of poison Ivy, poison oak, and poison sumac in order to avoid contact and prevent allergic contact dermatitis.  Poison ivy, the most common offender, grows on a vine and its leaves are usually present from May to July. Poison ivy leaves are green in the spring and reddish-orange in the fall. They are broad and spoon shaped leaves, and they cluster in groups of three. Poison ivy vines contain abundant amounts of urushiol oil and contact should be avoided, even if there are no poison ivy leaves present. The vines themselves, which can measure several inches in diameter, can be found running up pine trees and other trees and have a hairy appearance. The Urushiol oil can remain active for years so one must be careful around piles of cut wood or leaves. One must also be aware that a poison ivy rash or allergic contact dermatitis can occur after touching a dog or other pet that has been playing and running in the woods and whose hair has come in contact with the oil from poison ivy leaves.

Obviously, the best treatment for poison Ivy, poison oak, and poison sumac is to prevent exposure. When in the woods, or other areas where these poisonous plants grow, keep all skin covered. But, if contact has occurred, the skin should be washed immediately with soap or a solvent to prevent allergic contact dermatitis. A delay in washing off the oil as short as 5 or 10 minutes may be too late, as absorption into the deeper layer of skin occurs very quickly.

Regardless of whether the offending plant is poison ivy, poison oak, or poison sumac, contact dermatitis treatment is the same. Mild itching and discomfort of a poison ivy rash can be treated with cool compresses, calamine lotion, or 1% over-the-counter hydrocortisone cream or ointment. Mild cases generally run their course over several days. More severe cases, especially if there is allergic contact dermatitis with systemic involvement, may need to be treated with oral or injectable steroids. In severe cases of allergic contact dermatitis the rash may last from days to weeks.

Before heading out to the woods this spring and summer, The Online Allergist suggests that you look online for poison ivy pictures and poison oak pictures.  It would also be prudent to study poison sumac pictures, even though Poison Sumac is much less common.

The image below is one of the more illustrative poison ivy pictures.  It can help you identify what to avoid.





Studying poison oak pictures, like the one below, will help you prepare as well. 






The best poison ivy treatment is avoidance. So remember, “Leaves of three, let it be”.


If you know you are going to have to touch poison ivy you can use Tape Relief ( It is a barrier cream that will block allergens on any part of your skin it is applied to.

By Peter on 2012 04 25

Full of siaelnt points. Don’t stop believing or writing!

By Hayle on 2012 10 11

In fact, that the best thing about this film is how excellent
it’s as an epic quest film instead of how hilarious its.

By raspberry ketones on 2013 07 23

its very nice article, i like it and very important for every one, don’t be stop for writing

By Delly on 2013 08 18

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