The Facts About Poison Ivy, Sumac, and Oak

As we venture into the great outdoors this summer, poison ivy, poison sumac, and poison oak are potential joy-kills to be avoided. Simply coming into contact with these common plants can cause a rash that is not only unsightly, but also very itchy.

Leaves of three let it be at least when it comes to poison ivy  The Facts About Poison Ivy, Sumac, and Oak Photo

"Leaves of three, let it be" - at least when it comes to poison ivy (

So, needless to say, these plants are to be avoided. But how do you identify them? How do you know if your rash is a result of contact with one of these plants? And how do you treat the rash?

Here is everything you need to know about poison ivy, sumac, and oak:


  • Ivy – three pointed leaflets; the middle leaflet has a much longer stalk than the two side ones. The leaflet edges can be smooth or toothed but are rarely lobed. The leaves vary greatly in size, from 0.31 inches to 2.16 inches in length. They are reddish when they emerge in the spring, turn green during the summer, and become various shades of yellow, orange, or red in the autumn. Ivy grows as a vine.
  • Sumac – grows only in wetlands, smooth leaves, hairless stems, and 7-9 leaves per stem. Sumac grows as a small tree.
  • Oak – three leaflets with wavy edges, a glossy sheen on the top side of the leaf with a matte, velvety texture on their lower side, usually around 6 inches long; a shrub with white berries located near the flowers.

The Rash

  • Itchy skin
  • Redness or red streaks
  • Hives
  • Swelling
  • An outbreak of small or large blisters, often forming streaks or lines
  • Crusting skin (after blisters burst)
  • NOT contagious; the rash can only be spread by direct contact with urushiol, the oil found on these plants.


If you’re positive your rash is from posion ivy, sumac, or oak, and it only appears on a small section of your skin, you can treat it at home.

  • Rinse the oil off your skin immediately with luke warm water.
  • Wash all of the clothing you’re wearing when coming into contact with the plant.
  • Wash every surface that may have gotten the oil from the plants on it.
  • Treat the rash with oatmeal baths or baking soda baths, calamine lotion, cool compresses, cool showers, or antihistamine pills.

If you have any of the following symptoms, go to the emergency room immediately.

  • Trouble breathing or swallowing
  • Rash covers most of your body
  • You have many rashes or blisters
  • Swelling, especially if an eyelid swells shut
  • Rash develops anywhere on your face or genitals
  • Much of your skin itches or nothing seems to ease the itch

For help identifying whether your rash has been caused by poison ivy, sumac, or oak, see a dermatologist near you.

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