by Michele Blacksberg

Created on: August 05, 2009

Oh, and what a rash poison ivy can cause! Poison ivy is a vine-type plant that grows predominately east of the Rocky Mountains in the U.S. It is often recognized by the rhyme, "leaves of three let them be." There are other plants that appear similar to poison ivy such as Virginia Creeper and Box Elder but those plants do not cause the acute dermatitis rash of poison ivy.

In the Midwest, Northeast and in swampy areas of the Southeast poison sumac grows but it has 7-9 leaves. Poison oak grows more in the West and also has leaves of three. Poison ivy, poison sumac and poison oak all carry the same poisonous oil called uroshiol which is responsible for causing the offending rash. Just brushing against poison ivy will not cause an outbreak but the leaves are easily damaged allowing uroshiol to be released.

Uroshiol is impregnated in the leaves of these plants and is an irritant to the skin. Contact with uroshiol for as little as 10 minutes can set off the cascade of immune responses in the body causing an outbreak of uroshiol caused acute dermatitis. The body's immune response to the offending substance is to send special allergy cells called mast cells to the site. Mast cells release histamine and signal for other antigen-antibody responses to take place.

A rash develops in about 24-36 hours after exposure that is swollen and red; Blisters filled with fluid from dilated blood vessels are also common. The rash is extremely, sometimes intolerably itchy. Various topical products may relieve the itch of a full fledged rash such as: calamine lotion, oatmeal baths, topical cortisone and ice packs. Additionally, use of other products such as Zanfel or Tecnu can help halt the progression of the rash or even reverse it once it has started.

If exposed to poison ivy, you must, I repeat must, wash off the uroshiol oil within the first 15 min to avoid an outbreak of poison ivy. Washing off the oil might not be as easy as it seems since the oil is so adherent to the skin. The best way to remove uroshiol oil is to first clean using a solvent such as alcohol and wipe the area in a direction away from your face. Next strip your clothes off and take a shower carefully washing away with a good lather of soap. Clean shoes, tools and anything that came in contact with the poison ivy wearing gloves with alcohol. Uroshiol oil can stay active as long as 5 years on objects so a thorough cleaning is essential.

Most times the poison ivy rash will diminish in 3-4 wks. The greatest challenge in trying not to scratch too much but you cannot spread the rash by scratching contrary to what some believe. Contact a doctor if you find that you have broken out with a rash over much of your body especially if near your face or mouth or if an area becomes more swollen, discolored and painful since an infection may be starting.

Summertime is the most common time to get a poison ivy rash but the oil is still present in the fall when you can see the leaves turn crimson red like other fall foliage. Always be on the lookout for poison ivy when walking along trails or in woodsy backyards. Pets can also carry uroshiol oil on their fur so don't let your dogs run free in areas where poison ivy grows. Poison ivy is a vicious weed that will show no mercy given the chance to get a little urshiol in contact with your skin.

Most comprehensive site on Poison ivy:

http://poisonivy.aesir.com/view/welcome.html

www.netdoctor.co.uk/skin_hair/skin_immune_system_003 741.htm

http://www.associatedcontent.com/article/1876647/poi son_ivy_procedure_exposure_quick.html?cat=5

http://www.uis.edu/healthservices/links/PoisonIvyOak Sumac-.html

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