Poison Ivy

Poison ivy dermatitis is an allergic reaction that results from touching a poison ivy plant. There is also poison oak and poison sumac. The sap from any of these plants (or other objects that came in contact with the plant) creates the reaction, called contact dermatitis, on the skin. Sap can also remain underneath the fingernails for several days unless thoroughly washed with soap and water. The chemical oil that causes the allergic reaction is called urushiol.


Anyone can get poison ivy, oak or sumac as the plants may grow in many areas. Hikers, campers and people who work in the outdoors are more likely to come in contact with poison ivy. The chemical can be transmitted to the skin by direct contact with the leaves or by aerosolized portions from brush burning or mowing.

Unfortunately, poison ivy seems to be on the rise. The Wall Street Journal has reported that both leaf size and urushiol oil content on the plants are up significantly since the 1950s. The best precaution is to be aware of what these plants look like and to wear long pants and sleeves when in wooded areas.


Symptoms include itching and burning skin, redness, swelling and sometimes even blisters or hives. These symptoms can affect the eye and mouth areas as well as the skin, and usually appear within 8 to 48 hours after contact.

Poison ivy rashes are not contagious and cannot be spread by contact after a rash has appeared, as the urushiol has already left the skin. Rashes usually last from one to three weeks.  However, the oil can remain on objects, such as garden gloves, for several days.


The affected area should be washed immediately with soap and cold water, which can prevent or lessen the reaction if done within an hour of contact. Flush the eyes out with water to make sure there is no residue there. The use of cold water is important, as hot water will open the pores and let more of the oil in. You should also wash any potentially contaminated items such as clothing, gear or other items that may have come in contact with the plant.

An over-the-counter antihistamine may help relieve symptoms, and a steroid or anti-itch cream or calamine lotion can relieve the itching and burning. Most poison ivy rashes go away on their own within a few days, without long-term effect. However, if there is a severe reaction, any trouble breathing, or if the poisonous ingredients may have been breathed in or swallowed, immediate medical attention should be sought. Severe reactions are treated with oral or intramuscular steroid injections.