Version July 2025
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What are poison ivy, poison oak, and poison sumac? —
These are plants that can cause an itchy skin rash. When people have this rash, they often say something like "I got poison ivy."
The rash from these poisonous plants is very itchy and might form fluid-filled blisters. The blisters can show up in different places at different times. But that does not mean the rash is spreading. Touching the blisters or the fluid inside does not spread the rash. The rash should go away within 1 to 3 weeks.
The substance that causes the rash is found in other plant materials like the ginkgo fruit and mango peels.
How do people get a rash from these plants? —
You can get it if you:
●Touch a poison ivy, poison oak, or poison sumac plant
●Touch something that has the plant's oils on it (such as clothing, shoes, animal fur, or garden tools)
●Are nearby when these plants are being burned
What do poison ivy, poison oak, and poison sumac look like? —
Poison ivy and poison oak have 3 leaves coming off a single stem (figure 1). That's why there is a saying, "leaves of 3, let them be." The leaves start out green, but they can turn red or brown. Even dead plants can cause the rash.
Poison sumac has 5, 7, or more leaves on each stem.
How can I relieve the itching? —
You should do the following:
●Avoid scratching (this makes the itch worse). It can also cause irritation and make the rash last longer.
●To help with itching, you can:
•Add oatmeal to a cool or lukewarm bath.
•Apply cool compresses. Dip a clean cloth in cold water, and put it on the rash.
•Put calamine lotion on the rash.
•If your blisters have started to pop, use skin products that have aluminum acetate or "Burow's solution" in them (sample brand names: Dermeleve, Domeboro).
If you have a very bad rash, see your doctor or nurse. They might prescribe medicines called steroids. These can reduce swelling and relieve itching. They come as creams, ointments, or pills. Your doctor or nurse will decide what form you should use.
Steroid creams and ointments are also sold without a prescription. But non-prescription versions are not usually strong enough to help with poison ivy.
Some products can cause a reaction that makes your skin more itchy or irritated. Do not use these to treat a rash from one of these plants. They include antihistamine creams or lotions, numbing products with benzocaine, and antibiotic ointments with neomycin or bacitracin.
How can I avoid getting poison ivy again?
●Stay away from poison ivy, poison oak, and poison sumac, even if the plant is dead.
●Wear long sleeves and pants when working near poisonous plants. Wash your clothes right away when you are done.
●Wear thick vinyl gloves when doing yard work. (Latex and rubber gloves do not always protect against poisonous plants.)
●If you do touch a poisonous plant, gently wash the area as soon as possible. Do not rub or scrub. It might help to use a damp washcloth with liquid dish soap under running hot water.
●Do not burn poison ivy, poison oak, or poison sumac plants.
●Bathe your pets if they touch poisonous plants. Wear gloves when you bathe them. Pets do not get a rash, but if they get the oil on them, people could get a rash from touching their fur.
When should I call the doctor? —
Call your doctor or nurse if:
●You have a fever of 100.4°F (38°C) or higher, or chills.
●The rash spreads over large parts of your body, especially if it covers your face, is around your eyes, or is on your genitals.
●You have a lot of swelling.
●You are not sure if you have poison ivy.
●You have signs of a skin infection like swelling, redness, warmth, pain, or pus draining from the area of the rash.
●Your rash does not get better after 2 to 3 weeks.
Patient education: Contact dermatitis (The Basics)
Patient education: How to use topical medicines (The Basics)
Patient education: Poison ivy (Beyond the Basics)
Patient education: Contact dermatitis (including latex dermatitis) (Beyond the Basics)
