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Medical Author:

Daniel Jobe, MD

Coauthor:

Zoe Diana Draelos, MD, PA

Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

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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Symptoms of Poison Ivy, Oak, and Sumac Rash

• Exposure to poison ivy, oak, or sumac causes an itching rash that usually appears within 24-72 hours.

• The rash usually starts as small red bumps, and later develops blisters of variable size. The rash may crust or ooze.

• The rash may be found anywhere on the body that has contacted the oil from the plant. It can have any shape or pattern, but is often in straight lines or streaks across the skin.

• Different skin areas can break out at different times, making it seem as if the rash is spreading.

• Contrary to popular belief, leakage of blister fluid does not spread the rash. It is spread only by additional exposure to the oil, which often lingers on hands, clothing and shoes (which are often overlooked as carriers), or tools.