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Fact and fiction about poison ivy

A close encounter with this plant can mean trouble

One of the downsides of spending time in the great outdoors is that eventually, you're going to have a close encounter with poison ivy that will result in a painful rash that can easily spread over wide areas of your skin.

Poison ivy is a term often used to describe three types of poisonous plants: poison ivy, poison oak and sumac. All three can have the same results for people who are allergic to an oil contained in the plants. These plants tend to grow in wooded areas and if you don't spend much time there, you might not recognize the plants when you see them.

The saying “leaves of three, let them be” has been passed on from generation to generation to help you avoid contact with poison ivy, but in the case of sumac, the advice is worthless. True, poison ivy and oak have three leaves on a single stem but sumac can have 7 to 13 leaves on a single branch.

Urushiol oil

If you happen to be highly allergic to poison ivy, just brushing it against your skin will result in a rash within a few hours. The reason is the urushiol oil each plant contains. This substance is so potent it could also be a weapon of mass destruction. Experts say one one nanogram – one-billionth of a gram – can cause a skin rash.

A dead poison ivy plant might be five years old but the urushiol in it could still be active. That means you could be watching for three green leaves and completely miss the dead plant, since it would be unrecognizable.

Direct contact with urushiol is necessary to get the rash. However, if the plant is burned the oil is present in the smoke. If you are near the fire the oil in the smoke can cover your body and even enter your lungs.

If you are mowing at the edge of a wooded area or using a power trimmer, it's easy to become covered in poison ivy debris if your mower or trimmer comes in contact with it.

Not contagious

Another myth is that poison ivy is contagious. It will spread over your body from where you initially made contact with it but you can't spread it to someone else. That myth probably started because a poison ivy rash will produce a disgusting liquid when the blisters break.

However, if the urushiol oil is still on your hands and you touch someone else, you can spread it to that person. If your pet comes in contact with poison ivy while running through the woods, they won't get the rash but you can get it on your skin when you come in contact with them.

Not everyone reacts to poison ivy the same way. Some are almost hyper-sensitive, others hardly at all. Experts say almost no one is immune, however. Repeated exposure usually increases sensitivity.

Once you break out in a poison ivy rash, the agony can last for weeks. Without treatment it can take three weeks or more for a rash to clear up on its own. With treatment the healing process can take much less time.

Treatment for severe cases

According to the Mayo Clinic, mild cases of poison ivy may require no medical treatment. However, for widespread rashes, especially in sensitive areas, a doctor may prescribe corticosteroid pills, such as prednisone. For a severe case a doctor may give the patient a steroid shot. Some over-the-counter creams and ointments may provide relief from itching.

If you believe you have come in contact with poison ivy, you should thoroughly wash the area of skin with soap and water as quickly as possible. That may remove some of the urushiol oil and reduce the severity of the resulting rash.

When working in a wooded area that might have poison ivy wear gloves, long pants and long sleeves. And study photographs of poison ivy, poison oak and sumac so you can more easily avoid them.

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