Allergic rhinitis: Clinical manifestations, epidemiology, and diagnosis. Goldstein BG, et al. Approach to the patient with pustular skin lesions. Elmets CA. Polymorphous light eruption. Tinea versicolor. Swimmer's itch. American Osteopathic College of Dermatology. Riemann H, et al. Chigger bites. Clinical manifestations of Lyme disease in adults. Averill KM, et al. Wild parsnip Pastinaca sativa : A troublesome species of increasing concern. Weed Technology. Porter RS, et al. Contact dermatitis.
Merck Manual Professional Version. Ragweed allergy. Photosensitivity disorders photodermatoses : Clinical manifestations, diagnosis, and treatment. Tintinalli JE, et al. Heat emergencies. New York, N. Learn how to identify poison ivy, poison oak and poison sumac in all seasons. When hiking or engaging in other activities that might expose you to these plants, try to stay on cleared pathways. Wear socks, pants and long sleeves when outdoors. If camping, make sure you pitch your tent in an area free of these plants.
Keep pets from running through wooded areas so that urushiol doesn't stick to their fur, which you then may touch. Wash your skin or your pet's fur. Within 30 minutes after exposure to urushiol, use soap and water to gently wash off the harmful resin from your skin. Scrub under your fingernails too. Even washing after an hour or so can help reduce the severity of the rash. If you think your pet may be contaminated with urushiol, put on some long rubber gloves and give your pet a bath.
Clean contaminated objects. If you think you've come into contact with poison ivy, wash your clothing promptly in warm soapy water — ideally in a washing machine. Handle contaminated clothing carefully so that you don't transfer the urushiol to yourself, furniture, rugs or appliances.
Also wash as soon as possible any other items that came in contact with the plant oil — such as outdoor gear, garden tools, jewelry, shoes and even shoelaces. Urushiol can remain potent for years.
So if you put away a contaminated jacket without washing it and take it out a year later, the oil on the jacket may still cause a rash. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Overview Poison ivy rash Open pop-up dialog box Close. Poison ivy rash Brushing against a poison ivy plant can cause a red, itchy rash. Poison ivy rash on arm Open pop-up dialog box Close.
Poison ivy rash on arm Brushing against a poison ivy plant can cause bumps and blisters. Request an Appointment at Mayo Clinic. Poison ivy plant Open pop-up dialog box Close. Poison ivy plant A poison ivy plant typically has three leaflets branching off a single stem. Poison ivy plant with berries Open pop-up dialog box Close. The plant can be found in forests and wetlands, on beaches, and along streams, as well as in urban settings such as parks, yards, and along roads.
Poison ivy prefers partial sunlight, so it often grows where the land has been disturbed, such as along the edges of trails, fields, or landscaping.
There are two types of poison ivy — eastern and western — which have somewhat different geographic ranges but which look very similar and sometimes interbreed where their ranges overlap. Both types of poison ivy spread along the ground, and eastern poison ivy also climbs trees, shrubs, walls, fences, and other structures, clinging to its host with hairy rootlets and sometimes sending out horizontal branches.
Each poison ivy leaf or, more accurately, leaflet has a small leaf stem at its base, attaching it to a stalk or small branch that connects to the main poison ivy vine. The leaflet in the middle of the threesome usually has a longer leaf stem than the two side leaflets.
Poison ivy leaflets are about twice as long as they are wide. They are typically two to five inches long but may reach six or more inches if conditions are right. Poison ivy leaves may be smooth-edged or may have lobes or teeth. The two sides of the leaf may or may not be symmetrical.
Leaves may be red or green, shiny or dull. The plants may have flower buds, flowers, or berries in dense clusters close to the vine. According to the American Skin Association, as many as 50 million Americans have a poison ivy reaction each year.
Urushiol sticks to skin, clothing, fur, gardening tools, and other surfaces when it comes into contact with them. Washing the oil off your skin immediately after contact may prevent a rash from developing. Soap and water is effective, as are commercial poison ivy washes, but the key in either case is to wash the oil off quickly, before the allergic reaction begins. Following contact — or even potential contact — with poison ivy, you should also wash your clothing and footwear and any gear or equipment that could have touched the poison ivy plant.
Poison ivy loses its leaves in the winter and grows new ones in the spring. Young poison ivy leaves often start out dark red and shiny, then gradually turn green and less shiny over time. In addition to leaves, the poison ivy plant may grow clusters of small, green of flower buds in spring. In summer most poison ivy leaves are green, although new leaves may still appear reddish at first, and the leaf edges and stems of the plant sometimes stay red.
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