Poison ivy

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Poison ivy
2014-10-29 13 43 39 Poison Ivy foliage during autumn leaf coloration in Ewing, New Jersey.JPG
Poison ivy fall coloration
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Sapindales
Family: Anacardiaceae
Subfamily: Anacardioideae
Genus: Toxicodendron
Species

T. orientale Greene
T. radicans (L.) Kuntze
T. rydbergii (Small ex Rydb.) Greene

Contents

Poison ivy is a type of allergenic plant in the genus Toxicodendron native to Asia and North America. Formerly considered a single species, Toxicodendron radicans, poison ivies are now generally treated as a complex of three separate species: Toxicodendron radicans , Toxicodendron rydbergii , and Toxicodendron orientale . They are well known for causing urushiol-induced contact dermatitis, an itchy, irritating, and sometimes painful rash, in most people who touch them. The rash is caused by urushiol, a clear liquid compound in the plant's sap. They are variable in appearance and habit, and despite its common name, it is not a "true" ivy (Hedera), but rather a member of the cashew and pistachio family (Anacardiaceae). T. radicans is commonly eaten by many animals, and the seeds are consumed by birds, but poison ivy is most often thought of as an unwelcome weed.

Species

Three species of poison ivy are generally recognised; they are sometimes considered subspecies of Toxicodendron radicans: [1] [2] [3]

Description

Poison ivies can grow as small plants, shrubs, or climbing vines. [4] They are commonly characterized by clusters of leaves, each containing three leaflets, [4] hence the common expression "leaves of three, let it be". [5] These leaves can vary between an elliptic to egg shape and will have either smooth, lobed, or toothed margins. Additionally, the leaf clusters are alternate on the stem. Clusters of small, greenish flowers bloom from May to July and produce white berries in the fall a few millimeters in diameter. [6]

Health effects

A video describing the effects of poison ivy on the body
Blisters from contact with poison ivy Urushiol induced contact dermatitis.jpg
Blisters from contact with poison ivy

Urushiol-induced contact dermatitis is the allergic reaction caused by poison ivy. In extreme cases, a reaction can progress to anaphylaxis. Around 15 to 25 percent of people have no allergic reaction to urushiol, but most people have a greater reaction with repeated or more concentrated exposure. [7] [8]

Over 350,000 people are affected by urushiol annually in the United States. [9]

The oozing fluids released by scratching blisters do not spread the poison. The fluid in the blisters is produced by the body and it is not urushiol itself. [10] The appearance of a spreading rash indicates that some areas received more of the poison and reacted sooner than other areas or that contamination is still occurring from contact with objects to which the original poison was spread.[ citation needed ]

Those affected can unknowingly spread the urushiol inside the house, on phones, door knobs, couches, counters, desks, and so on, thus in fact repeatedly coming into contact with poison ivy and extending the length of time of the rash. If this happens, the surfaces should be wiped with bleach or a commercial urushiol removal agent. The blisters and oozing result from blood vessels that develop gaps and leak fluid through the skin; if the skin is cooled, the vessels constrict and leak less. [11] If plant material with urushiol is burned and the smoke then inhaled, this rash will appear on the lining of the lungs, causing extreme pain and possibly fatal respiratory difficulty. [10] If poison ivy is eaten, the mucus lining of the mouth and digestive tract can be damaged. [12]

Urushiol oil can remain active for several years, so handling dead leaves or vines can cause a reaction. In addition, oil transferred from the plant to other objects (such as pet fur) can cause the rash if it comes into contact with the skin. [13] [10] Clothing, tools, and other objects that have been exposed to oil should be washed to prevent further reactions. [14]

Treatment

Immediate washing with soap and cold water or rubbing alcohol may help prevent a reaction. [15] During a reaction, calamine lotion or diphenhydramine may help mitigate symptoms. Corticosteroids, either applied to the skin or taken by mouth, may be appropriate in extreme cases. An astringent containing aluminum acetate (such as Burow's solution) may also provide relief and soothe the uncomfortable symptoms of the rash. [16]

Urushiol binds to the skin on contact where it causes severe itching that develops into reddish inflammation or uncoloured bumps, and then blistering. These lesions may be treated with calamine lotion, Burow's solution compresses, dedicated commercial poison ivy itch creams, or baths to relieve discomfort, [17] though recent studies have shown some traditional medicines to be ineffective. [18] [19] Over-the-counter products to ease itching—or simply oatmeal baths and baking soda—are now recommended by dermatologists for the treatment of poison ivy. [20]

A plant-based remedy cited to counter urushiol-induced contact dermatitis is jewelweed, though jewelweed extracts had no positive effect in clinical studies. [21] [22] [23] [24] Others argue that prevention of lesions is easy if one practices effective washing, using plain soap, scrubbing with a washcloth, and rinsing three times within 2–8 hours of exposure. [25]

The pentadecyl catechols of the oleoresin within the sap of poison ivy and related plants causes the allergic reaction; the plants produce a mixture of pentadecylcatechols, which collectively is called urushiol. After injury, the sap leaks to the surface of the plant where the urushiol becomes a blackish lacquer after contact with oxygen. [26] [27]

Prognosis

Typically, the rash from the urushiol oil lasts about five to twelve days, but in extreme cases it can last a month or more. [28] A urushiol rash usually develops within a week of exposure and can last 1–4 weeks, depending on severity and treatment. In rare cases, urushiol reactions may require hospitalization. [10]

People who are sensitive to urushiol can also experience a similar rash from mangoes. Mangoes are in the same family (Anacardiaceae) as poison ivy; the sap of the mango tree and skin of mangoes has a chemical compound similar to urushiol. [29] A related allergenic compound is present in the raw shells of cashews. [30] Similar reactions have been reported occasionally from contact with the related fragrant sumac ( Rhus aromatica ) and Japanese lacquer tree. These other plants are also in the family Anacardiaceae.[ citation needed ]

Similar allergenic plants

Related Research Articles

<span class="mw-page-title-main">Anacardiaceae</span> Family of flowering plants that includes cashew and mango

The Anacardiaceae, commonly known as the cashew family or sumac family, are a family of flowering plants, including about 83 genera with about 860 known species. Members of the Anacardiaceae bear fruits that are drupes and in some cases produce urushiol, an irritant. The Anacardiaceae include numerous genera, several of which are economically important, notably cashew, mango, Chinese lacquer tree, yellow mombin, Peruvian pepper, poison ivy, poison oak, sumac, smoke tree, marula and cuachalalate. The genus Pistacia is now included, but was previously placed in its own family, the Pistaciaceae.

<i>Toxicodendron</i> Genus of plants

Toxicodendron is a genus of flowering plants in the sumac family, Anacardiaceae. It contains trees, shrubs and woody vines, including poison ivy, poison oak, and the lacquer tree. All members of the genus produce the skin-irritating oil urushiol, which can cause a severe allergic reaction. The generic name is derived from the Greek words τοξικός (toxikos), meaning "poison," and δένδρον (dendron), meaning "tree". The best known members of the genus in North America are poison ivy (T. radicans), practically ubiquitous throughout most of eastern North America, and western poison oak, similarly ubiquitous throughout much of the western part of the continent.

<i>Toxicodendron radicans</i> Species of plant

Toxicodendron radicans, commonly known as eastern poison ivy or poison ivy, is an allergenic flowering plant that occurs in Asia and eastern North America. The species is well known for causing urushiol-induced contact dermatitis, an itchy, irritating, and sometimes painful rash, in most people who touch it. The rash is caused by urushiol, a clear liquid compound in the plant's sap. The species is variable in its appearance and habit, and despite its common name, it is not a true ivy (Hedera), but rather a member of the cashew and pistachio family (Anacardiaceae). T. radicans is commonly eaten by many animals and the seeds are consumed by birds, but poison ivy is most often thought of as an unwelcome weed. It is a different species from western poison ivy, T. rydbergii, which has similar effects.

<span class="mw-page-title-main">Sumac</span> Related species of plants in the family Anacardiaceae

Sumac or sumach is any of about 35 species of flowering plants in the genus Rhus and related genera in the cashew family (Anacardiaceae). Sumacs grow in subtropical and temperate regions throughout every continent except Antarctica and South America. Sumac is used as a spice, as a dye, and in medicine.

<span class="mw-page-title-main">Urushiol</span> Oily mixture of organic compounds

Urushiol is an oily mixture of organic compounds with allergenic properties found in plants of the family Anacardiaceae, especially Toxicodendronspp., Comocladia spp. (maidenplums), Metopium spp. (poisonwood), and also in parts of the mango tree as well as the fruit of the cashew tree.

<i>Impatiens</i> Genus of flowering plants

Impatiens is a genus of more than 1,000 species of flowering plants, widely distributed throughout the Northern Hemisphere and the tropics. Together with the genus Hydrocera, Impatiens make up the family Balsaminaceae.

<span class="mw-page-title-main">Contact dermatitis</span> Human disease

Contact dermatitis is a type of acute or chronic inflammation of the skin caused by exposure to chemical or physical agents. Symptoms of contact dermatitis can include itchy or dry skin, a red rash, bumps, blisters, or swelling. These rashes are not contagious or life-threatening, but can be very uncomfortable.

<i>Toxicodendron diversilobum</i> Species of plant

Toxicodendron diversilobum, commonly named Pacific poison oak or western poison oak, is a woody vine or shrub in the sumac family, Anacardiaceae. It is widely distributed in western North America, inhabiting conifer and mixed broadleaf forests, woodlands, grasslands, and chaparral biomes. Peak flowering occurs in May. Like other members of the genus Toxicodendron, T. diversilobum causes itching and allergic rashes in most people after contact by touch or smoke inhalation. Despite its name, it is not closely related to oaks, nor is it a true tree.

Antipruritics, abirritants, or anti-itch drugs, are medications that inhibit the itching often associated with sunburns, allergic reactions, eczema, psoriasis, chickenpox, fungal infections, insect bites and stings like those from mosquitoes, fleas, and mites, and contact dermatitis and urticaria caused by plants such as poison ivy or stinging nettle. It can also be caused by chronic kidney disease and related conditions.

<i>Toxicodendron vernix</i> Species of plant

Toxicodendron vernix, commonly known as poison sumac, or swamp-sumach, is a woody shrub or small tree growing to 9 metres (30 feet) tall. It was previously known as Rhus vernix. This plant is also known as thunderwood, particularly where it occurs in the southern United States. All parts of the plant contain a resin called urushiol that causes skin and mucous membrane irritation to humans. Urushiol is the same chemical that poison ivy is covered in. When the plant is burned, inhalation of the smoke may cause the rash to appear on the lining of the lungs, causing extreme pain and possibly fatal respiratory difficulty.

Burow's solution is an aqueous solution of aluminium triacetate. It is available in the U.S. as an over-the-counter drug for topical administration, with brand names including Domeboro, Domeboro Otic, Star-Otic, and Borofair. The preparation has astringent and antibacterial properties and may be used to treat a number of skin conditions, including insect bites and stings, rashes caused by poison ivy and poison sumac, swelling, allergies, and bruises. However, its main use is for treatment of otitis, including otomycosis.

<span class="mw-page-title-main">Urushiol-induced contact dermatitis</span> Medical condition

Urushiol-induced contact dermatitis is a type of allergic contact dermatitis caused by the oil urushiol found in various plants, most notably sumac family species of the genus Toxicodendron: poison ivy, poison oak, poison sumac, and the Chinese lacquer tree. The name is derived from the Japanese word for the sap of the Chinese lacquer tree, urushi. Other plants in the sumac family also contain urushiol, as do unrelated plants such as Ginkgo biloba.

<span class="mw-page-title-main">Allergic contact dermatitis</span> Medical condition

Allergic contact dermatitis (ACD) is a form of contact dermatitis that is the manifestation of an allergic response caused by contact with a substance; the other type being irritant contact dermatitis (ICD).

<i>Toxicodendron rydbergii</i> Species of plant

Toxicodendron rydbergii, the western poison ivy or northern poison oak, is a species of Toxicodendron in the cashew family native to North America.

<i>Toxicodendron pubescens</i> Eastern poison oak

Toxicodendron pubescens, commonly known as Atlantic poison oak, or eastern poison oak, is an upright shrub that can grow to 1 metre (3 feet) tall. Its leaves are 15 centimetres (6 inches) long, alternate, with three leaflets on each. The leaflets are usually hairy and are variable in size and shape, but most often resemble white oak leaves; they usually turn yellow or orange in autumn. The fruit is small, round, and yellowish or greenish. It is not closely related to true oaks.

<i>Toxicodendron vernicifluum</i> Species of plant

Toxicodendron vernicifluum, also known by the common name Chinese lacquer tree, is an Asian tree species of genus Toxicodendron native to China and the Indian subcontinent, and cultivated in regions of China, Japan and Korea. Other common names include Japanese lacquer tree, Japanese sumac, and varnish tree. The trees are cultivated and tapped for their toxic sap, which is used as a highly durable lacquer to make Chinese, Japanese, and Korean lacquerware.

<span class="mw-page-title-main">Tecnu</span>

Tecnu is an over-the-counter skin cleanser manufactured by Tec Laboratories, a pharmaceutical company based in Albany, Oregon. It is intended for use by humans and furry pets after topical exposure to urushiol, the active ingredient in poison oak, poison ivy, and poison sumac. Tecnu is made from deodorized mineral spirits, water, propylene glycol, octylphenoxy-polythoxethanol, mixed fatty acid soap, and fragrance.

<i>Mangifera indica</i> Species of flowering plant in the cashew family Anacardiaceae

Mangifera indica, commonly known as mango, is a species of flowering plant in the family Anacardiaceae. It is a large fruit tree, capable of growing to a height of 30 metres. There are two distinct genetic populations in modern mangoes – the "Indian type" and the "Southeast Asian type".

<i>Lithraea caustica</i> Species of plant

Lithraea caustica is a species of flowering plants in the soapberry family Anacardiaceae. This plant is endemic to central Chile; an example occurrence is in the area of La Campana National Park and Cerro La Campana. The tree is a well known human allergen and can cause a rash of the skin, the effects of and susceptibility to which can vary greatly among individuals.

<span class="mw-page-title-main">Aluminium diacetate</span> Chemical compound

Aluminium diacetate, also known as basic aluminium acetate, is a white powder with the chemical formula C4H7AlO5. It is one of a number of aluminium acetates and can be prepared in a reaction of sodium aluminate (NaAlO2) with acetic acid.

References

  1. ↑ "Toxicodendron rydbergii". Plants of the World Online. Royal Botanic Gardens, Kew . Retrieved 19 October 2020.
  2. ↑ "Toxicodendron orientale". Plants of the World Online. Royal Botanic Gardens, Kew . Retrieved 19 October 2020.
  3. ↑ "Toxicodendron radicans". Plants of the World Online. Royal Botanic Gardens, Kew . Retrieved 19 October 2020.
  4. 1 2 3 4 5 Innes, Robin J. (2012). "Toxicodendron radicans, T. rydbergii". Fire Effects Information System (FEIS). US Department of Agriculture (USDA), Forest Service (USFS), Rocky Mountain Research Station, Fire Sciences Laboratory.
  5. ↑ "LEAVES OF THREE, LET IT BE: HOW TO AVOID POISON IVY AND ITS ITCHY RASH". Reconnect with Nature. Forest Preserve District of Will County. Retrieved 19 October 2020.
  6. ↑ "Ohio Weedguide". Oardc.ohio-state.edu. Retrieved 2022-08-27.
  7. ↑ "How Poison Ivy Works". HowStuffWorks. 23 September 2005.
  8. ↑ Rohde, Michael. "Contact-Poisonous Plants of the World". mic-ro.com. Archived from the original on 2010-07-02. Retrieved 2020-10-19.
  9. ↑ Chaker, Anne Marie; Athavaley, Anjali (June 22, 2010). "Least-Welcome Sign of Summer". The Wall Street Journal . p. D1.
  10. 1 2 3 4 "Frequently Asked Questions about Poison Ivy, Oak, and Sumac". poison-ivy.org. 25 February 2015.
  11. ↑ Editors of Prevention (2010). The Doctors Book of Home Remedies: Quick Fixes, Clever Techniques, and Uncommon Cures to Get You Feeling Better Fast. Rodale. pp. 488–. ISBN   978-1-60529-866-5.
  12. ↑ Lewis, Robert Alan (1998). Lewis' dictionary of toxicology. CRC Press. pp. 901–. ISBN   978-1-56670-223-2.
  13. ↑ "Poison Ivy, Oak & Sumac". aad.org. Archived from the original on 2007-07-08.
  14. ↑ "Poison ivy - oak - sumac". MedlinePlus Medical Encyclopedia. A.D.A.M., Inc. Retrieved 16 June 2019.
  15. ↑ "Misconceptions About Treating Poison Ivy and Oak Rash". teclabsinc.com. Archived from the original on 2014-08-26.
  16. ↑ Gladman, Aaron C. (June 2006). "Toxicodendron Dermatitis: Poison Ivy, Oak, and Sumac". Wilderness & Environmental Medicine. 17 (2): 120–128. doi: 10.1580/PR31-05.1 . PMID   16805148.
  17. ↑ Wilson, W. H. & Lowdermilk, P. (2006). Maternal Child Nursing Care (3rd edition). St. Louis: Mosby Elsevier.
  18. ↑ "American Topics. An Outdated Notion, That Calamine Lotion". Archived from the original on 2007-06-19. Retrieved 2007-07-19.
  19. ↑ Appel, L.M. Ohmart; Sterner, R.F. (1956). "Zinc oxide: A new, pink, refractive microform crystal". AMA Arch Dermatol. 73 (4): 316–324. doi:10.1001/archderm.1956.01550040012003. PMID   13301048.
  20. ↑ "American Academy of Dermatology – Poison Ivy, Oak & Sumac". Archived from the original on 2009-06-05.
  21. ↑ Long, D.; Ballentine, N. H.; Marks, J. G. (1997). "Treatment of poison ivy/oak allergic contact dermatitis with an extract of jewelweed". Am. J. Contact. Dermat. 8 (3): 150–3. doi:10.1097/01206501-199709000-00005. PMID   9249283.
  22. ↑ Gibson, MR; Maher, FT (1950). "Activity of jewelweed and its enzymes in the treatment of Rhus dermatitis". Journal of the American Pharmaceutical Association. 39 (5): 294–6. doi:10.1002/jps.3030390516. PMID   15421925.
  23. ↑ Guin, J. D.; Reynolds, R. (1980). "Jewelweed treatment of poison ivy dermatitis". Contact Dermatitis. 6 (4): 287–8. doi:10.1111/j.1600-0536.1980.tb04935.x. PMID   6447037. S2CID   46551170.
  24. ↑ Zink, B. J.; Otten, E. J.; Rosenthal, M.; Singal, B. (1991). "The effect of jewel weed in preventing poison ivy dermatitis". Journal of Wilderness Medicine. 2 (3): 178–182. doi:10.1580/0953-9859-2.3.178. S2CID   57162394.
  25. ↑ Extreme Deer Habitat (2014-06-22). "How to never have a serious poison ivy rash again". YouTube . Archived from the original on 2021-12-21. Retrieved 2016-07-26.
  26. ↑ Barceloux, Donald G. (2008). Medical Toxicology of Natural Substances: Foods, Fungi, Medicinal Herbs, Plants, and Venomous Animals. John Wiley and Sons. pp. 681–. ISBN   978-0-471-72761-3.
  27. ↑ Rietschel, Robert L.; Fowler, Joseph F.; Fisher, Alexander A. (2008). Fisher's contact dermatitis. PMPH-USA. pp. 408–. ISBN   978-1-55009-378-0.
  28. ↑ "Poison Ivy, Poison Oak and Poison Sumac FAQs".
  29. ↑ Tucker, Mark O.; Swan, Chad R. (1998). "The Mango–Poison Ivy Connection". New England Journal of Medicine. 339 (4): 235. doi:10.1056/NEJM199807233390405. PMID   9673302.
  30. ↑ Rosen, T.; Fordice, D. B. (April 1994). "Cashew Nut Dermatitis". Southern Medical Journal. 87 (4): 543–546. doi:10.1097/00007611-199404000-00026. PMID   8153790.
  31. ↑ "Botanical Dermatology – ALLERGIC CONTACT DERMATITIS – ANACARDIACEAE AND RELATED FAMILIES". The Internet Dermatology Society, Inc. Retrieved 22 Sep 2014.
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