Poison sumac (Toxicodendronvernix) contains a rash-inducing oil calledurushiol.
The urushiol oil that causes poison sumac rash is also found in poison ivy and poison oak.
All three plants are part of theToxicodendrongenus.
Grb / Getty Images
The leaves, stems, flowers, and roots of these poisonous plants can cause itchyToxicodendrondermatitis.
However, poison sumac rash is often more severe than those resulting from poison ivy or oak.
Grb / Getty Images
What Are the Symptoms of Poison Sumac?
Reproduced with permission from © DermNetdermnetnz.org2023.
This photo contains content that some people may find graphic or disturbing.
Reproduced with permission from DermNetdermnetnz.org2023.
Common symptoms experienced by individuals with poison sumac rash include:
How Common is Poison Sumac Allergy?
Poison sumac rash is self-limiting, meaning it heals itself, and usually resolves in under a month.
How to Identify Poison Sumac
Poison sumac looks like a woody shrub or small tree.
A full-grown poison sumac tree can be 20 feet tall.
In June and July, poison sumac has yellowish-green flowers.
By September, grayish-white berries can be seen dangling.
Poison sumac often grows along pond edges or riverbanks with the tree’s roots visibly immersed in shallow water.
Even when environmental conditions are hospitable to poison sumac, it’s still fairly rare.
If effectively removed within 10 minutes of skin contact, urushiol won’t likely trigger an allergic reaction.
The rash and watery blisters associated with poison sumac are not contagious once the urushiol oil is gone.
Are There Complications of a Poison Sumac Rash?
Skin infection is the most common complication of poison sumac rash.
Scratching itchy skin can create open sores or wounds vulnerable to bacteria.
Urushiol smoke exposure may lead to morbidity and, in rare cases, can even cause death.
Summary
Poison sumac can cause a red, itchy rash that often blisters.
Any urushiol oil that isn’t properly washed off is like a contagion and spreads rash-causing allergens.
Poison ivy, poison oak, and poison sumac all contain the same rash-inducing oil.
However, the urushiol oil in poison sumac can cause a more severe allergic reaction.
Gladman AC.Toxicodendrondermatitis: poison ivy, oak, and sumac.Wilderness & Environmental Medicine.
2023;34(3):388-392. doi:10.1016/j.wem.2023.03.001
Labib A, Yosipovitch G.ItchyToxicodendronplant dermatitis.Allergies.
American Academy of Dermatology Association.Poison ivy, oak, and sumac: How to treat the rash.
2014;6(6):429-434. doi:10.14740/jocmr1855w
New York State Department of Transportation.Poison Sumac (Toxicodendron vernix).
USDA.Toxicodendron vernix(L.) Kuntze.
Monroe J.Toxicodendron contact dermatitis: A case report and brief review.J Clin Aesthet Dermatol.
2020;13(9 Suppl 1):S29-S34.
Kaiser Permenante.Poison ivy, oak, or sumac: Tips for washing.
NIOSH Fast Facts.Protecting Yourself From Poisonous Plants.
FDA.Outsmarting poison ivy and other poisonous plants.
2022;43(4):359-362. doi:10.1097/PAF.0000000000000777
CCD: NIOSH Science Blog.Outdoor Workers and Poisonous Plant Exposures.
