Poison Ivy and Oak
Poison Ivy and Oak
19 Skin-Soothing Remedies
If you're like most people allergic to poison ivy and poison oak (it's the most common allergy in the country, claiming at least half the population), you may not even know you've picked it up until the next day, when you are scratching like a hound at a rash of exquisite itchability.
The nagging itch and telltale red rash are caused by the toxin urushiol oil, which is found in both poison ivy and poison oak. Some people are more sensitive to it than others. And some are not sensitive to it at all—they can literally roll in the stuff and not get a reaction. But our experts don't advise those of you lucky enough to be immune to give it a try. A sensitivity to urushiol can develop at any time. The solutions to poison ivy or poison oak are substances that annihilate urushiol. But remember—what works for someone else may not work for you, and in severe cases may not work at all.
Urushiol Oil: Evil and Persistent
Urushiol oil, the active ingredient in poison ivy and poison oak, is "one of the most potent external toxins we know," says William L. Epstein, M.D. "The amount needed to cause a rash in very sensitive people is measured in nanograms, and it could take as little as 1 nanogram. But most sensitive people will react in the 100-nanogram range." Consider that a nanogram is a mere billionth of a gram; that means it would take less than 1/4 ounce of urushiol to cause a rash in every person on earth. Five hundred people could itch from the amount covering the head of a pin.
"I'm surprised it hasn't been used as a nonlethal chemical warfare weapon," says James A. Duke, Ph.D., whose interest in "this evil plant" was sparked by "an early ethnobotanical application of poison oak as a substitute for toilet paper."
Its itch torments you; its long life can fool you. Dr. Duke says "specimens of poison ivy several centuries old" have caused dermatitis in sensitive people.
"When the Japanese restored the gold leaf on the golden Temple in Kyoto, they painted urushiol lacquer on it to preserve and maintain the gold," Dr. Epstein says. "The main message for American tourists there is, 'Don't try to steal the gold.' " You'll be caught red-handed. Literally.
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KILLING THE ITCH
If you've been messing around in a poison patch, you'll soon know whether you're immune or not. And as ugly as the rash looks, it's the itch that'll do you in. Here's what you can do about it, starting with the universal remedy.
Get cozy with darlin' calamine. The time-honored mainstay in poison treatment is calamine lotion, a popular skin protectant with a soothing action "that produces cooling and distracts your skin from the itching sensation," says Robert Rietschel, M.D., chairman of the Department of Dermatology at New Orleans' Ochsner Clinic in Louisiana, and clinical professor of dermatology at Louisiana State University School of Medicine. "In poison ivy and poison oak, the blood vessels develop gaps that leak fluid through the skin, causing blisters and oozing," he explains. "When you cool the skin, the vessels constrict and don't leak as much."
Calamine lotion also leaves a powdery residue that absorbs the oozing, develops a crust, and keeps it from sticking to your clothes, Dr. Rietschel notes. He suggests applying calamine lotion three or four times a day. To keep your rash from getting too dry and making the itch even worse, stop using calamine when the oozing stops, he says.
MEDICAL ALERT
Signs of an Emergency
About 15 percent of the 120 million Americans who are allergic to poison oak and poison ivy are so highly sensitive they break out in a rash and begin to swell in 4 to 12 hours instead of the normal 24 to 48. Their eyes may swell shut and blisters may erupt on their skin.
"This is one of the few true emergencies in dermatology," says William L. Epstein, M.D. "Get to a hospital as soon as possible. A shot of corticosteroids will bring the swelling down."
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Subtract the additives. Antihistamines like Benadryl and painkillers like benzocaine and lidocaine are often added to certain calamine lotion products. "They may work for some people," says William L. Epstein, M.D., a professor of dermatology at the University of California, San Francisco, School of Medicine, "but they don't add much relief vis-ˆ-vis the cost, and you run the risk of developing an allergic rash from the additives."
Pop a pill. Oral antihistamines, however, are a different story. In fact, they're high up on Dr. Rietschel's list. There are two over-the-counter brands to choose from: Chlor-Trimeton, which contains the active ingredient chlorpheniramine maleate, and Benadryl, which contains the active ingredient diphenhydramine hydrochloride. "You could take your hay fever medicine if it happens to be an antihistamine," Dr. Rietschel says.
Try other drying agents. "Although not as popular and soothing as calamine, there are other skin soothers that can be just as effective. Some of them, however, often have a lot of alcohol and tend to sting," Dr. Rietschel warns. Use them as you would calamine—until the oozing stops. Otherwise you can get the rash too dry, and it will crack and cause more itching. Zinc oxide, witch hazel, Burow's solution (aluminum acetate), and baking soda are common topical drying agents.
Cover with a compress. Put a cotton cloth soaked in cool water over the rash and let a fan blow over it, Dr. Rietschel advises. The cooling/evaporating effect works the same as calamine lotion, although there's no residue to soak up the oozing.
Irritate it to distraction. "Counterirritants like menthol and phenol confuse the nerve endings in the skin and give a cooling sensation," Dr. Rietschel says. "But they can sting and sometimes aren't sufficient to give you the relief you need." Menthol and phenol are available in anti-itch creams.
Counterattack early with cortisone. The OTC cortisone creams are too weak and "are absolutely worthless in knocking out a significant rash," Dr. Rietschel says. "But they can relieve minimal itching." Dr. Epstein recommends them as "pretty good about two weeks into the rash, when it's healing and scaling and itching."
Try an oatmeal onslaught. Colloidal oatmeal dries up oozing blisters. Aveeno is the most popular commercial preparation for skin care and comes with easy-to-follow instructions. Apply it with a cloth to the blisters, or use it in the bath if you don't mind the mess and a very slippery tub.
Get folksy with herbs. The most popular herbal treatment is jewelweed, also known as impatiens or touch-me-not, says Purdue University professor of pharmacognosy and author of The Honest Herbal, Varro E. Tyler, Ph.D. "There's little solid research, but in one clinical trial it worked just as well as prescription cortisone creams," he says. You can slit the stem and put the juice on the rash. U.S. Department of Agriculture economic botanist James A. Duke, Ph.D., says he uses impatiens to stop the rash from developing. "I ball up the whole plant and make sort of a washrag out of it and wipe the poison sap off," he says.
Apply plant potions. Another natural remedy is said to be the leaf of the black nightshade plant (not to be confused with the deadly nightshade). "Chop, grind, or crush it up, mix it with milk or cream, and apply it to the rash," Dr.Tyler says. He says other people have found success using the juice of the milkweed plant. "Just drip the milky latex on the rash."
Polish it off. Maybe not so natural is white shoe polish, which Dr. Tyler reports, contains pipe clay that has effects similar to calamine. Apply it as you would calamine. He says pipe clay can be found in "the old-fashioned shake-it-up kind" of polish. Another ingredient in shoe polish that has the same effect is zinc oxide.
NEVER, NEVER AGAIN!
You can try to avoid poison ivy or poison oak simply be steering clear of it—if you know what it looks like. Generally, the plants have clusters of three shiny leaves, the source of the couplet "Leaves of three, let it be." Different regions of the country, however, have different varieties. And in the winter there are no leaves to let be, but the poison lurks in roots and stems, waiting to pounce. Then there are your dog and cat, Simon and Garfunkel, who can bring the stuff on their coats right into your living room.
Thankfully, Mother Nature, the drug industry, and the cosmetics industry each provide substances that may stop the poisonous substance, urushiol, from causing a rash even after exposure to the plant.
Rub out the bad guy. Washing your exposed skin in lots of rubbing alcohol after you're finished playing in poison ivy for the day takes the urushiol oil out of your skin, Dr. Epstein says. But don't use a washcloth to apply alcohol—"it just picks it up [the urushiol oil] and spreads it around," Dr. Epstein says.
Wait till you're finished being exposed. Never dab alcohol on during your hike or picnic, because it removes your protective skin oils and the exposure you get to the poison around the next bend will be worse.
Rinse well. "Water inactivates urushiol," Dr. Epstein says. Soap is unnecessary. But after being exposed, you must douse yourself immediately with water from your hose or canteen or the next stream. "The best possible treatment is alcohol followed by water," he says. Again, don't use a washcloth.
Wash everything. That means everything that might have come in contact with the poisonous plant: your clothes, your dog, your backpack. Dr. Epstein says one patient who drove home after handling poison oak "kept picking it up for weeks from the steering wheel of his car."
Spray before you play. Most deodorants contain an organically activated clay known as organoclay to hold the other ingredients in suspension; almost all antiperspirants have the clay plus aluminum chlorohydrate. Both of these have been found by Dr. Epstein to be highly effective at neutralizing urushiol.
Since products designed to prevent poison ivy and poison oak are under the scrutiny of the Food and Drug Administration, Dr. Epstein suggests that in the meantime you may want to spray your favorite deodorant or antiperspirant on your arms, legs, clothes, and pets before rolling in poison. He says antiperspirants are best because they contain both ingredients. "The aluminum salts work better than the organoclays, but they're irritating, so don't spray antiperspirants on your face or body folds," he cautions.
The Alternate Route
Anything Goes in a Pinch
Horse urine. Paint thinner. Acetone. Ammonia. Clear nail polish. Meat tenderizer. Sound appetizing? Don't worry, you don't have to drink them. They've all been used successfully to treat skin exposed to poison ivy or poison oak because that's all people had handy at the time.
"Organic solvents like ammonia, paint thinner, and acetone are very good for getting the urushiol oil out of your skin before the rash occurs," says William L. Epstein, M.D. Other solvents that work are hypo solfite, used in photographic darkrooms, and bleach, Dr. Epstein says. He warns, however, that they should be used only as a last resort. "Putting solvents on your skin isn't recommended for normal use. Still, if that's all you have, it's better than nothing. Just don't use them every day, or you can get a worse rash than poison oak. Solvents also extract all your natural protective skin oils."
But for getting the urushiol off your tools, car upholstery, and other places you suspect are contaminated, nothing beats solvents.
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Hold up a shield. Multi-Shield is a barrier skin cream that's been used in industries as a defense against oils and solvents handled by employees in their work. And now it's being tested to prevent poison ivy and poison oak. Dr. Epstein did "very limited tests" and gave it a passing grade. It works for mild cases of poison. It can be purchased through Interpro, Inc., P.O. Box 1823, Haverhill, MA 01831.
Don't get burned. Don't try to rid your yard of urushiol by burning plants—urushiol takes to the air in a fire. you can inhale droplets of the oil and come down with serious lung infections, fever, and a body-wide rash. That's why you also don't want to hang around forest fires.
PANEL OF ADVISERS
James A. Duke, Ph.D., is an economic botanist for the Agricultural Research Service of the U.S. Department of Agriculture.
William L. Epstein, M.D., is chairman emeritus and professor of dermatology at the University of California, San Francisco, School of Medicine.
Robert Rietschel, M.D., is chairman of the Department of Dermatology at the Ochsner Clinic in New Orleans, Louisiana, and clinical professor of dermatology at the Louisiana State University School of Medicine and Tulane University in New Orleans.
Varro E. Tyler, Ph.D., is a professor of pharmacognosy at Purdue University in West Lafayette, Indiana, and the author of The Honest Herbal. He also serves as a Prevention magazine adviser.
