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Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• Poison ivy, oak, and sumac facts
• What causes the rash? How do I identify poison ivy, oak, and sumac?
• What are the signs and symptoms of the poison ivy rash?
• Is a rash from poison ivy, oak, and sumac dermatitis contagious?
• What are risk factors for poison ivy, oak, and sumac dermatitis?
• How is the dermatitis of poison ivy, oak, and sumac diagnosed?
• What is the treatment for poison ivy, oak, and sumac dermatitis?
• What are complications for poison ivy, oak, and sumac dermatitis?
• What is the prognosis (outlook) for poison ivy, oak, and sumac dermatitis?
• How can contact with poison ivy, oak, and sumac be prevented?
• What should people do if they are exposed to a poisonous plant?
• Find a local Dermatologist in your town
• Poison Ivy Index

The rash from poison ivy, oak, or sumac is not contagious. It cannot be spread to other parts of the body or to other people. However, if you still have traces of the plant oil (urushiol) on your hands after exposure, you can spread it to other people and to other parts of your body. Sometimes, the rash will take longer to appear in some areas of the body than in others, giving the appearance that the reaction has spread elsewhere in the body. However, only contact with the sap oil urushiol can spread the reaction, and the rash itself does not contain urushiol.

Risk factors include being in outdoor areas where the plants may be present. These plants are present throughout the U.S., except for desert areas, higher elevations (above 4,000 feet), Alaska, and Hawaii. It has been estimated that about 75% of people have some degree of sensitivity to urushiol, but the degree of sensitivity varies among individuals.

The diagnosis is generally established upon observation of the typical rash in an area that could have been exposed to the plants, along with a history of potential exposure (such as weeding a garden or walking in the woods). No special tests are required for the diagnosis. In some cases, skin inflammation due to other causes (including allergic contact dermatitis or chemical irritation) may be mistaken for poison ivy, oak, or sumac since the rash may be similar.