Poison ivy, poison oak, and poison sumac are plants that can cause a skin rash upon contact. The red, itchy rash often shows up in lines or streaks. It may cause fluid-filled blisters or large, raised hives.
The rash is caused by an allergic reaction to an oil in these plants. The rash may occur when you touch the plant or when you touch objects that have come in contact with these plants. Common examples include clothing, pet fur, sporting gear, or gardening tools.
You can't catch or spread the rash by touching the rash or the blister fluid. The plant oil will already have been absorbed or washed off the skin. The rash may seem to be spreading because it's still developing from earlier contact or because you have touched something that still has the plant oil on it.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.
How can you care for yourself at home?
If your doctor prescribed a cream, use it as directed. If your doctor prescribed medicine, take it exactly as prescribed. Call your doctor if you think you are having a problem with your medicine.
Use cold, wet cloths to reduce itching.
Take warm or cool baths with oatmeal bath products, such as Aveeno.
Keep cool, and stay out of the sun.
Leave the rash open to the air.
Wash all clothing or other things that may have come in contact with the plant oil.
Avoid most lotions and ointments until the rash heals. Calamine lotion may help relieve symptoms of a plant rash. Use it 3 or 4 times a day.
To prevent exposure
If you know you will be working around poison ivy, oak, or sumac:
Use a cream or lotion to help prevent the plant oil from getting on your skin. These products are available over the counter.
Apply the product less than 1 hour before contact with the plant, in a thick, complete layer.
Wash it off thoroughly within 4 hours or as soon as possible after contact with plants. The product only delays the oil from getting into your skin.
Be sure to wash your hands before and after you use the restroom.
When should you call for help?
Call your doctor now or seek immediate medical care if:
Your rash gets worse, and you start to feel bad and have a fever, a stiff neck, nausea, and vomiting.
You have signs of infection, such as:
Increased pain, swelling, warmth, or redness.
Red streaks leading from the rash.
Pus draining from the rash.
A fever.
Watch closely for changes in your health, and be sure to contact your doctor if:
You have new blisters or bruises, or the rash spreads and looks like a sunburn.
The rash gets worse, or it comes back after nearly disappearing.
You think a medicine you are using is making your rash worse.
Your rash does not clear up after 1 to 2 weeks of home treatment.
You have joint aches or body aches with your rash.
Clinical Review Board All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
Clinical Review Board All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
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The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.
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