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poison ivy: Media
plant
Videos
Why does poison ivy make people so itchy?
Learn how the oil urushiol, secreted by poison ivy (Toxicodendron radicans),...
Why scratching an itch actually makes it worse
Understanding the chemical process of itching and why scratching is futile.
Images
allergy
An allergic contact dermatitis reaction caused by exposure to poison ivy.
© Joy Brown/Shutterstock.com
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