Have you ever heard this old saying? “Leaves of three? Let them be!” If you haven’t, it’s good advice! Knowing how to recognize poison ivy can make a camping trip or any outdoors adventure much better.

Toxicodendron radicans — more commonly known as poison ivy — is a poisonous plant known for the itching rash it can cause. The sap within the plant contains a clear liquid called "urushiol."

It’s the urushiol that causes the allergic reaction that up to 80 percent of people experience after exposure to poison ivy.

Poison ivy is not really an ivy at all. However, its appearance resembles ivy. Found all over the United States, poison ivy can be difficult to identify at times.

Poison ivy can be found growing in three different forms: a trailing vine, a shrub or a climbing vine that grows on trees, fences, buildings, etc. It can be found anywhere, from your backyard to the woods to the sides of highways.

Poison ivy blends in well with other plants, so you have to be careful when you’re hiking in the woods or walking anywhere with a lot of plants.

If you’re wondering whether a plant is poison ivy, look for these clues:

1. clusters of three leaves (“leaves of three”) 2. shiny (not fuzzy) leaves that are smooth 3. no thorns

Poison ivy can look different depending on the season. Leaves that start off red or light green can turn darker green as they mature, before turning red, yellow or orange in the fall.

Two other poisonous plants that also contain urushiol are poison oak and poison sumac. Keep an eye out for these plants, too!

Poison ivy can also be hard to identify because there are many plants with “leaves of three.” If you’re not sure, don’t touch it. It’s best to play it safe when it comes to poison ivy!

So what should you do if you suspect you’ve come into contact with poison ivy? Wash your skin with soap and water as soon as possible. If possible, take a hot, soapy shower.

The urushiol oil is what causes an allergic reaction when absorbed into your skin. If you can wash it off soon enough (within 10 minutes of contact), you may be able to avoid an allergic reaction and a bad, itchy rash.

You should also wash any clothes, shoes, garden tools or pets that may have come into contact with poison ivy. urushiol oil on your clothes, your shovel or your dog can cause a rash if you touch them later.

The oil can stay on unwashed items for a very long time. It’s not uncommon to get a poison ivy rash from shoes that you may have worn when you stepped on poison ivy last summer!

Once you have an allergic reaction to poison ivy that turns into an itchy rash, there’s not a whole lot you can do other than treat the skin and try to minimize the discomfort. Cold showers and calamine lotion can help, as can oatmeal baths. More serious cases may require a visit to the doctor to get an antihistamine or steroid shot to decrease itching and swelling.

Contrary to the beliefs of many, the oozing fluids that are sometimes released from the blisters caused by poison ivy do not spread the poison. urushiol is the only thing that can cause the allergic reaction.

Once it binds to your skin, it is absorbed and cannot be transferred to another person. So, once you shower after being exposed to poison ivy, it’s not contagious and can’t be passed on to another person.

Curiously, people sensitive to poison ivy sometimes experience a similar rash from mangoes. Mangoes are in the same family as poison ivy, and the sap of the mango tree and the skin of mangoes contain a chemical similar to urushiol.

 

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