Poison Ivy, Oak, or Sumac
What are poison ivy, oak, and sumac?
What causes a poison ivy, oak, or sumac rash?
The rash is caused by contact with a sticky oil called urushiol (say "yoo-ROO-shee-all") found in poison ivy, oak, or sumac. You can get the rash from:
The rash is only spread through the oil. You can't catch a rash from someone else by touching the blister fluid.
The rash is an allergic reaction to the oil. You become allergic to it through contact. After you have come in contact with these plants, your immune system may start to react to the oil as though it's a harmful substance.
What are the symptoms?
The usual symptoms of the rash are:
Some people are very allergic to the oil. In these people, even a little bit of the oil may cause serious symptoms such as:
The rash usually takes more than a week to show up the first time you have a reaction to the oil. It develops in a day or two on later contacts. The rash may form in new areas over several days, but you will only get a rash where the oil touched your skin.
The rash usually lasts about 10 days to 3 weeks. But it may last up to 6 weeks in more severe cases.
How is the rash diagnosed?
A doctor can usually diagnose the rash by looking at it and asking questions about:
How is it treated?
If you get a mild rash, you can take care of it at home.
Do not use the following medicines. They can cause allergy problems of their own:
See your doctor if the rash covers a large area of your body or your symptoms are severe. A doctor may prescribe a corticosteroid cream to help clear up the rash. A severe rash may be treated with corticosteroid pills or shots.
How can you prevent the rash from poison ivy, oak, and sumac?
If you think you have touched any of these plants:
The best way to prevent future rashes is to learn to identify these plants and avoid them.
When you can't avoid contact with the plants:
eMedicineHealth Medical Reference from Healthwise
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