Medical & Surgical Dermatology
Poison Ivy, Oak, and SumacFlorida’s beautiful foliage is really something special. There are so many great things to see in nature, but some of it is not meant to be enjoyed up-close. Poisonous plants definitely fall into this category. One tiny drop of urushiol, the toxic oil in poison ivy, oak, and sumac, is enough to cause a red, itchy, uncomfortable rash on your skin. The more contact your skin has with urushiol, the more severe your reaction.
Generally, these kinds of rashes can be treated at home with over-the-counter topicals, but more serious cases need the assistance of a dermatologist, so if you consider your condition to be unbearable or you experience troubling swelling, make an appointment with a Water’s Edge Dermatology practitioner.
Ways of Getting Poisonous Plant Rashes
Touching a plant that contains urushiol
Urushiol can stick to almost anything. Touching a pet's fur, a gardening tool, or sports equipment that contains urushiol can cause the rash.
Burning poisonous plants releases particles of urushiol into the air. These airborne particles can land on the skin.
The rash is not contagious, so anyone who helps apply cream, for example, is not at risk, unless the urushiol is still on your skin. That’s unlikely because your skin absorbs the oil in a matter of minutes. However, if someone touches clothing or another item that still has the oil on it, they could suffer a reaction. This is more likely because the oil can hang around for quite some time.
People who spend a lot of time outdoors are more at risk. These include:· Landscapers
· Forest firefighters and forestry workers
· Electrical linemen
· People who install fences
· Maintenance workers in parks, gardens, and nurseries
· Hikers, campers, rafters, kayakers, and fishermen
Normal Symptoms of Poisonous Plant Rashes
· Itchy skin where the plant touched you
· Red streaks or general redness where the plant brushed against your skin
· Small bumps or larger raised areas
· Blisters filled with fluid that may leak out
Serious Symptoms of Poisonous Plant Rashes
· Swelling of the face, mouth, neck, genitals, or eyelids, which may prevent the eyes from opening
· Widespread, large blisters that ooze large amounts of fluid
· Blood-filled blisters that may become black and shiny
· Infection can develop, especially with excessive scratching
The first time you get urushiol on your skin, it may take a week for a rash to appear, but any subsequent run-ins will trigger rashes more quickly, in some cases within a few hours.
Any skin that came into contact with the oil is at risk for the rash. The rash may seem to be spreading, but all that means is it’s still developing from earlier contact or you’ve touched something that still has urushiol on it.
What to do for Poisonous Plant Rashes
There’s wide variation in the duration of a rash. If you can act quickly after exposure, you can actually reduce the severity or may avoid an outbreak altogether.If you think you may have come into contact with poison ivy, oak, or sumac, immediately wash areas of the skin that may have touched the plant. You could also try using Tecnu or Zanfel, two topicals that are designed to remove the oil from your skin.
Urushiol can remain active for a long time, so be sure to thoroughly launder all clothing and everything else that might be contaminated.
If you break out in a rash, you’ll want to seek relief with antihistamine pills, calamine or aloe vera lotion, or cold compresses. Soaking the area in cool water may also be soothing. Never use hot water as that will open up the pores and allow more oil to seep into your skin. For all the naturalists out there, try these:
· Cucumber slices directly on the affected skin
· Apple cider vinegar soaked in a brown paper bag
· Baking soda paste
· Witch hazel
· Oatmeal bath
· Rubbing alcohol - apply immediately after exposure to prevent the oil from penetrating your skin· Juice from a lemon - apply immediately after exposure
If you have a moderate to severe rash, visit Water's Edge Dermatology. One of our practitioners may prescribe corticosteroid creams, ointments, gels, or shots.
How to Recognize Poison Ivy, Poison Oak, and Poison Sumac
The saying, “Leaves of three, beware of me,” can help identify poison ivy and oak, but a more accurate saying is “leaflets of three, beware of me."
Each leaf on poison ivy and poison oak has three smaller leaflets. The middle leaflet has a longer stalk than the two on the sides. In the spring, poison ivy develops yellow-green flowers.
Poison sumac can be identified by its row of hairless, paired leaflets that contains an additional leaflet at the end. Each stem has seven to nine leaves.
Often the leaves of these plants have spots that resemble blotches of black enamel paint. These spots are made up of urushiol, which turn brownish black when exposed to air. Before urushiol is exposed to the air, it is colorless or pale yellow.
Come early fall, the leaves on some of these poisonous plants turn yellow or red. The fruit of mature plants often turns off-white.
Poison Ivy by Region
Poison ivy grows as a vine in the East, Midwest, and South. In the far Northern and Western United States, Canada, and around the Great Lakes, it grows as a shrub.
Poison Oak by Region
In the West, poison oak may grow as a vine, but it’s usually a shrub. In the East, it grows as a shrub.
Poison Sumac by Region
Poison sumac grows into a small tree. It’s thankfully not very common since it only grows in wet areas. You’ll find it in peat bogs in the Northeast and Midwest and in swampy areas in parts of the Southeast.
Preventing Allergic ReactionsAvoiding toxic plants is the best thing you can do. Other recommendations include:
· Wearing long pants, long sleeves, boots, and gloves when it’s not possible to avoid these plants
· Applying an over-the-counter skin-barrier product that contains bentoquatam before going outdoors. Bentoquatam helps prevent urushiol from penetrating the skin.
For more information, visit this CDC site.
Poison ivy, oak, and sumac contain an oil called urushiol (you-ROO-shee-all). When this oil touches the skin, many people develop an allergic reaction that causes a rash.
There are three ways to get this rash:
Touching a plant that contains urushiol.
Urushiol can stick to almost anything. Touching a pet's fur, gardening tool, or sports equipment that contains urushiol can cause the rash.
Burning these poisonous plants releases particles of urushiol into the air. These airborne particles can land on the skin.
Recognizing These Poisonous PlantsThe saying, “Leaves of three, beware of me,” can help identify poison ivy and oak, but a more accurate saying is “leaflets of three, beware of me.” Each leaf on poison ivy and poison oak has three smaller leaflets. The middle leaflet has a longer stalk than the two on the sides.
Poison sumac can be identified by its row of paired leaflets that contains an additional leaflet at the end. Often the leaves have spots that resemble blotches of black enamel paint. These spots are made up of urushiol, which when exposed to air turn brownish black. Before urushiol is exposed to the air, it is colorless or pale yellow.
Poison ivy grows as vines or low shrubs. Poison oak, with its oak-like leaves, is a shrub. Poison sumac is a tall shrub or small tree. In the spring, poison ivy develops yellow-green flowers. Come early fall, the leaves on some of these poisonous plants turn yellow or red. The plants with berry-like fruit also can change. On the mature plants, the fruit often turns off-white.
Urushiol begins to penetrate the skin in minutes, but the rash usually takes time to appear. Typically, 12 to 72 hours pass before the person experiences severe itching, redness, and swelling, followed by small or large blisters. When the rash develops after a plant touches the skin, streaks or lines often reveal where the plant brushed against the skin. The rash can appear on any part of the body. It might seem to spread, but this is a delayed reaction. The rash does not spread and is not contagious.
Poison IvyPoison ivy grows as a vine in the East, Midwest, and South. In the far Northern and Western United States, Canada, and around the Great Lakes, it grows as a shrub. Each leaf has three leaflets.
Poison OakIn the West, poison oak may grow as a vine but usually is a shrub (pictured). In the East, it grows as a shrub. It has three leaflets to form its leaves.
Poison SumacPoison sumac grows in standing water in peat bogs in the Northeast and Midwest, and in swampy areas in parts of the Southeast. Each leaf has seven to 13 leaflets.
Developing a RashThe first time urushiol touches the skin, an allergic reaction seldom occurs. With repeated exposure, sensitivity to urushiol develops. Sensitivity varies from person to person. About 85 percent of people develop an allergic reaction when adequately exposed to poison ivy. Only about 15 percent seem to be resistant. Sensitivity to poison ivy tends to decline with age, and people who reach adulthood without developing a sensitivity have a 50 percent chance of developing an allergic reaction to poison ivy, oak, and sumac. Children who have reacted usually find that their sensitivity decreases by young adulthood. People who were once allergic to poison ivy may even lose their sensitivity entirely later in life.
Prevention of Poison IvyAvoiding contact is best. Dermatologists recommend:
- Recognizing and avoiding these poisonous plants.
- Wearing long pants, long sleeves, boots, and gloves when it is not possible to avoid these plants.
- Applying an over-the-counter skin-barrier product that contains bentoquatum before going outdoors. Bentoquatum helps prevent urushiol from penetrating the skin.
TreatmentWhen an allergic reaction develops, wash the skin well with lukewarm water and soap. Thoroughly launder all clothing and everything else that might be contaminated because urushiol can remain active for a long time.
For mild cases, cool showers and an over-the-counter product that eases itching can be effective. Oatmeal baths and baking-soda mixtures also can sooth the discomfort. When a severe reaction develops contact a dermatologist immediately, or go to an emergency room. Prescription medication might be needed to reduce the swelling and itch