The oil in poison ivy/oak/sumac plants (called urushiol) can cause an allergic rash in 60% to 80% of people who come into contact with it.
Mild rashes can be treated at home, and mostly cause discomfort from itching, burning, or blistering. Severe, widespread rashes require medical treatment.
Reviewed by: Steven Dowshen, MD
Date reviewed: April 2014
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