How to Identify, Prevent and Treat Poison Oak and Ivy

How to Identify, Prevent and Treat Poison Oak, Ivy and Sumac From WEBMD "What causes a poison ivy, oak, or sumac rash? The rash is caused by contact with an oil (urushiol) found in poison ivy, oak, or sumac. The oil is present in all parts of the plants, including the leaves, stems, flowers, berries, and roots. Urushiol is an allergen, so the rash is actually an allergic reaction to the oil in these plants. Indirect contact with urushiol can also cause the rash. This may happen when you touch clothing, pet fur, sporting gear, gardening tools, or other objects that have come in contact with one of these plants. But urushiol does not cause a rash on everyone who gets it on his or her skin. What are the symptoms of the rash? The usual symptoms of the rash are: Itchy skin where the plant touched your skin. Red streaks or general redness where the plant brushed against the skin. Small bumps or larger raised areas (hives). Blisters filled with fluid that may leak out. The rash usually appears 8 to 48 hours after your contact with the urushiol. But it can occur from 5 hours to 15 days after touching the plant.1 The rash usually takes more than a week to show up the first time you get urushiol on your skin. But the rash develops much more quickly (within 1 to 2 days) after later contacts. The rash will continue to develop in new areas over several days but only on the parts of your skin that had contact with the urushiol or those parts where the urushiol was spread by touching ...