Poison Ivy     THIS ARTICLE IS MEANT TO BE  A REFERENCE ONLY SEE YOUR DOCTOR IMMEDIATELY IF YOU SEE SYMPTOMS.   Poison ivy is a harmful vine or shrub in the cashew family. It grows plentifully in parts of the United States and southern Canada . Poison ivy usually grows as a vine twining on tree trunks or straggling over the ground. But the plant often forms upright bushes if it has no support to climb upon. Species related to poison ivy include poison oak, which grows in the Pacific Northwest and nearby regions of Canada , and poison sumac, which grows in the Eastern United States . Poison oak and poison sumac both are shrubs. The tissues of all these plants contain a poisonous oil somewhat like carbolic acid. This oil is extremely irritating to the skin. It may be brushed onto the clothing or skin of people coming in contact with the plants. Many people have been poisoned merely by taking off their shoes after walking through poison ivy. People can get poisoned from other people, but only if the oil remains on their skin. The eruptions themselves are not a source of infection. Appearance - the leaves of poison ivy are red in early spring. Later in spring, they change to shiny green. They turn yellow, red or orange in autumn. Each leaf is made up of three leaflets more or less notched at the edges. Two of the leaflets form a pair on opposite sides of the leafstalk, while the third stands by itself at the tip of the leafstalk. Small greenish flowers grow in bunches attached to the main stem close to where each leaf joins it. Later in the season, clusters of poisonous, berry-like drupes form. They are whitish, with a waxy look. Control and treatment: Efforts have been made to destroy these plants by uprooting them or by spraying them with chemicals. But poison ivy and poison oak are so common that such methods have not been very effective in eliminating them. Contact with the plants should be avoided. After the oil has touched the skin, it usually takes some time for it to penetrate and do its damage. Before this happens, it is wise to wash the skin thoroughly several times with plenty of soap and water. Care should be taken not to touch any part of the body, for even tiny amounts of the oil will cause irritation. If poisoning develops, the blisters and red, itching skin may be treated with dressings of calamine lotion, Epsom salts, or bicarbonate of soda. Scientists have developed a vaccine that can be injected or swallowed. But this is effective only if taken before exposure.   Approximately 85 percent of the population will develop an allergic reaction if exposed to poison ivy, oak or sumac, according to the American Academy of Dermatology. Nearly one-third of forestry workers and firefighters who battle forest fires in California , Oregon and Washington develop rashes or lung irritations from contact with poison oak, which is the most common of the three in those states. Usually, people develop a sensitivity to poison ivy, oak or sumac only after several encounters with the plants, sometimes over many years. However, sensitivity may occur after only one exposure. The cause of the rash, blisters, and infamous itch is urushiol (pronounced oo-roo-shee-ohl), a chemical in the sap of poison ivy, oak and sumac plants. Because urushiol is inside the plant, brushing against an intact plant will not cause a reaction. But undamaged plants are rare. "Poison oak, ivy and sumac are very fragile plants," says. Stems or leaves broken by the wind or animals, and even the tiny holes made by chewing insects, can release urushiol. Reactions, treatments and preventive measures are the same for all three poison plants. Avoiding direct contact with the plants reduces the risk but doesn't guarantee against a reaction. Urushiol can stick to pets, garden tools, balls, or anything it comes in contact with. If the urushiol isn't washed off those objects or animals, just touching them--for example, picking up a ball or petting a dog--could cause a reaction in a susceptible person. (Animals, except for a few higher primates, are not sensitive to urushiol.) Urushiol that's rubbed off the plants onto other things can remain potent for years, depending on the environment. If the contaminated object is in a dry environment, the potency of the urushiol can last for decades, says Epstein. Even if the environment is warm and moist, the urushiol could still cause a reaction a year later. "One of the stories I tell people is of the hunter who gets poison oak on his hunting coat," says Epstein. "He puts it on a year later to go hunting and gets a rash [from the urushiol still on the coat]." Almost all parts of the body are vulnerable to the sticky urushiol, producing the characteristic linear (in a line) rash. Because the urushiol must penetrate the skin to cause a reaction, places where the skin is thick, such as the soles of the feet and the palms of the hands, are less sensitive to the sap than areas where the skin is thinner. The severity of the reaction may also depend on how big a dose of urushiol the person got.   Quick Action Needed   Because urushiol can penetrate the skin within minutes, there's no time to waste if you know you've been exposed. "The earlier you cleanse the skin, the greater the chance that you can remove the urushiol before it gets attached to the skin," says Hon-Sum Ko, M.D., an allergist and immunologist with FDA's Center for Drug Evaluation and Research. Cleansing may not stop the initial outbreak of the rash if more than 10 minutes has elapsed, but it can help prevent further spread. If you've been exposed to poison ivy, oak or sumac, if possible, stay outdoors until you complete the first two steps: ·                           First, Epstein says, cleanse exposed skin with generous amounts of isopropyl (rubbing) alcohol. (Don't return to the woods or yard the same day. Alcohol removes your skin's protection along with the urushiol and any new contact will cause the urushiol to penetrate twice as fast.) ·                           Second, wash skin with water. (Water temperature does not matter; if you're outside, it's likely only cold water will be available.) ·                           Third, take a regular shower with soap and warm water. Do not use soap before this point because "soap will tend to pick up some of the urushiol from the surface of the skin and move it around," says Epstein. ·                           Clothes, shoes, tools, and anything else that may have been in contact with the urushiol should be wiped off with alcohol and water. Be sure to wear gloves or otherwise cover your hands while doing this and then discard the hand covering.   Dealing with the Rash   If you don't cleanse quickly enough, or your skin is so sensitive that cleansing didn't help, redness and swelling will appear in about 12 to 48 hours. Blisters and itching will follow. For those rare people who react after their very first exposure, the rash appears after seven to 10 days. Because they don't contain urushiol, the oozing blisters are not contagious nor can the fluid cause further spread on the affected person's body. Nevertheless, Epstein advises against scratching the blisters because fingernails may carry germs that could cause an infection. The rash will only occur where urushiol has touched the skin; it doesn't spread throughout the body. However, the rash may seem to spread if it appears over time instead of all at once. This is either because the urushiol is absorbed at different rates in different parts of the body or because of repeated exposure to contaminated objects or urushiol trapped under the fingernails. The rash, blisters and itch normally disappear in 14 to 20 days without any treatment. But few can handle the itch without some relief. For mild cases, wet compresses or soaking in cool water may be effective. Oral antihistamines can also relieve itching. FDA also considers over-the-counter topical corticosteroids (commonly called hydrocortisones under brand names such as Cortaid and Lanacort) safe and effective for temporary relief of itching associated with poison ivy. For severe cases, prescription topical corticosteroid drugs can halt the reaction, but only if treatment begins within a few hours of exposure. "After the blisters form, the [topical] steroid isn't going to do much," says Epstein. The American Academy of Dermatology recommends that people who have had severe reactions in the past should contact a dermatologist as soon as possible after a new exposure. Severe reactions can be treated with prescription oral corticosteroids. There are a number of OTC products to help dry up the oozing blisters, including: ·                           aluminum acetate (Burrows solution) ·                           baking soda ·                           Aveeno (oatmeal bath) ·                           aluminum hydroxide gel ·                           calamine ·                           kaolin ·                           zinc acetate ·                           zinc carbonate ·                           zinc oxide Desensitization, vaccines, and barrier creams have been studied over the last several decades for their potential to protect against poison ivy reactions, but none have been approved by FDA for this purpose. Right now, prevention seems the best treatment.     Getting Rid of the Plants   Poison ivy, oak and sumac are most dangerous in the spring and summer, when there is plenty of sap, the urushiol content is high, and the plants are easily bruised. However, the danger doesn't disappear over the winter. Dormant plants can still cause reactions, and cases have been reported in people who used the twigs of the plant for firewood or the vines for Christmas wreaths. Even dead plants can cause a reaction, because urushiol remains active for several years after the plant dies. If poison ivy invades your yard, "there's really no good news for you," says David Yost, a horticulturist (specialist in fruits, vegetables, flowers, and general gardening) with the state of Virginia . The two herbicides most commonly used for poison ivy--Roundup and Ortho Poison Ivy Killer--will kill other plants as well. Spraying Roundup (active ingredient glyphosate) on the foliage of young plants will kill the poison ivy, but if the poison ivy vine is growing up your prize rhododendron or azalea, for example, the Roundup will kill them too, he says. Ortho Poison Ivy Killer (active ingredient triclopyr), if used sparingly, will kill poison ivy but not trees it grows around, says Joseph Neal, Ph.D., associate professor of weed science, Cornell University. "But don't use it around shrubs, broadleaf ground cover, or herbaceous garden plants," he says. Neal explains it is possible to spray the poison ivy without killing other plants if you pull the poison ivy vines away from the desirable plants and wipe the ivy foliage with the herbicide, or use a shield on the sprayer to direct the chemical. If you don't want to use chemicals, "manual removal will get rid of the ivy if you're diligent," says Neal. You must get every bit of the plant--leaves, vines, and roots--or it will sprout again. The plants should be thrown away according to your municipality's regulations, says Neal. Although urushiol will break down with composting, Neal doesn't recommend that because the plants must be chopped into small pieces first, which just adds to the time you're exposed to the plant and risk of a rash. "It's a health issue," he says. Never burn the plants. The urushiol can spread in the smoke and cause serious lung irritation. The American Academy of Dermatology recommends that whenever you're going to be around poison ivy--trying to clear it from your yard or hiking in the woods--you wear long pants and long sleeves and, if possible, gloves and boots. Neal recommends wearing plastic gloves over cotton gloves when pulling the plants. Plastic alone isn't enough because the plastic rips, and cotton alone won't work because after a while the urushiol will soak through. Identification Please   Unfortunately, poison ivy, oak and sumac don't grow with little picture ID badges around their stems, so you have to know what to look for. The famous rule "leaves of three, let it be" is good to follow, except that some of the plants don't always play by the rules and have leaves in groups of five to nine. To avoid these plants and their itchy consequences, here's what to look for.   Poison Ivy ·                           grows around lakes and streams in the Midwest and the East ·                           woody, ropelike vine, a trailing shrub on the ground, or a free-standing shrub ·                           normally three leaflets (groups of leaves all on the same small stem coming off the larger main stem), but may vary from groups of three to nine ·                           leaves are green in the summer and red in the fall ·                           yellow or green flowers and white berries