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Distinguish between poison ivy and other leafy plants. Learn what grows in your area. Check your skin for a rash. Wear protective clothing. Watch where your pets wander. Apply an ivy-block barrier.

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Poison ivy usually grows as a vine or a shrub and has clumps of three leaves. You may have heard the rhyme, “Leaves of three, let it be.”  But other plants also grow as three leaves from a single stem (like blackberry, raspberry, and box elder). The main difference is that in the poison ivy plant, the middle or central leaf grows from a longer single stem. Poison ivy is usually glossy and the leaves might have red stems or reddish leaves. To determine if a plant is poison ivy, look for hairy tendrils on the main vine. These let the plant climb and grow. Poison ivy plants can grow all year long and throughout most of the United States. For example, your region may have poisonous sumac or oak. The following regions have these poisonous plants:  Eastern poison ivy: these vines grow on the ground and can climb Western poison ivy: these vines only grow on the ground Pacific poison oak: this grows as a shrub, ground vine, and climbing vine Atlantic poison oak: this is a ground vine and shrub (but not very common) Poison sumac is a small tree usually found in wet areas If you've come into contact with poison ivy, a rash will appear within minutes to hours (12 to 24 hours) of touching the oily allergen (urushiol). The rash will usually be red, itchy and swollen. Your rash might also have streaks if you brushed against the plant. The fluid-filled blisters can also form, but they don't spread the rash. Don't be surprised if it takes up to three days for a poison ivy rash to develop. If you know you'll be hiking in an area with poison ivy or you'll be clearing the plant from your yard, wear clothing that prevents the oil from brushing against your skin. Wear long pants and shirts, socks, boots, and vinyl gloves. If your clothes have come into contact with poison ivy, wash your clothing as soon as you can and avoid touching the clothes with bare hands. You should also wash your shoes and any outdoor gear you used to clear the poison ivy. If you have a pet that likes to romp through the brush or lives outdoors, be aware that they could potentially carry the oil on their fur. If the oil comes into contact with their skin (the belly of a dog, for instance), your pet may also suffer a rash. But if they just brush by the plant and get the oil on their fur, they will not be affected. If you go to pet or hold them, however, you will be exposing yourself to the oil and may suffer a rash.  Try to keep an eye on your pets when they are outdoors. If you see them come into contact with poison ivy, wear protective gloves and give them a bath to remove the oil from the fur and prevent them from spreading it. Before going on a walk in the woods, you may want to apply a skincare product that prevents poison ivy oil from getting on your skin. You can purchase an ivy-block barrier from a drugstore. Look for a product that contains a 5% solution of bentoquatam. Apply the thick cream 15 minutes before you'll be encountering poison ivy. Reapply the ivy-block barrier every four hours. To remove the cream, wash it off using soap and water. Avoid using the barrier cream on kids under six years old.