What are poison ivy, oak, and sumac?
Poison ivy, poison oak, and poison sumac are plants that can cause a skin rash called allergic contact dermatitis when they touch your skin. The red, uncomfortable, and itchy rash often shows up in lines or streaks and is marked by fluid-filled bumps (blisters) or large raised areas (hives). It is the most common skin problem caused by contact with plants (plant dermatitis).
