Poison Ivy, Oak, and Sumac

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Poison ivy, oak, and sumac facts

  • Poison ivy, poison oak, and poison sumac are plants than can cause an itchy rash upon contact.
  • A substance called urushiol, found in these plants, causes the rash.
  • The rash is not contagious.
  • The rash usually disappears in one to three weeks.
  • The majority of cases can be treated at home.

What are poison ivy, poison oak, and poison sumac?

Poison ivy, poison oak, and poison sumac are plants that can cause a rash if individuals come in contact with the oily resin found in them.

Poison ivy (Toxicodendron radicans -- eastern poison ivy/Toxicodendron rydbergii -- western poison ivy) typically grows as a vine or shrub, and it can be found throughout much of North America (except in the desert, Alaska, and Hawaii). It grows in open fields, wooded areas, on the roadside, and along riverbanks. It can also be found in urban areas, such as parks or backyards. Poison ivy plants typically have leaf arrangements that are clustered in groups of three leaflets, though this can vary. The color and shape of the leaves may also vary depending upon the exact species, the local environment, and the time of year. The plant may have yellow or green flowers, and white to green-yellow berries, depending on the season.

Picture of poison ivy
Picture of poison ivy

Poison oak (Toxicodendron diversilobum) grows as a vine or shrub, and it is found in the western United States and British Columbia. It also has a leaf arrangement similar to poison ivy, with clusters of three leaflets. The leaves may sometimes resemble true oak leaves.

Picture of poison oak
Picture of poison oak

Poison sumac (Toxicodendron vernix) grows as a shrub or small tree, and it is found in the eastern/southeastern United States. It grows in very wet areas, and it can be found along the banks of the Mississippi River. Each stem contains seven to 13 leaves arranged in pairs. It has the potential to cause a more severe rash than either poison ivy or poison oak.

Picture of poison sumac
Picture of poison sumac
Medically Reviewed by a Doctor on 4/20/2015

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Poison Ivy, Oak, and Sumac - Treatment Question: What treatments were effective for your poison ivy, oak, or sumac rash?
Poison Ivy, Sumac, and Oak - Home Remedies Question: What home remedies helped alleviate the symptoms and sign of your poison ivy, oak, or sumac rash?
Poison Ivy - Experience Question: Please describe your experience with poison ivy.
Poison Ivy - Symptoms and Signs Question: What symptoms and signs were associated with your poison ivy rash?
Poison Ivy - Prevention Question: What do you do prevent exposure to poisonous plants such as poison ivy, oak, and sumac?
Read about poison ivy, oak, and sumac treatment and prevention.

Poison Ivy Treatment and Rash Prevention

Common Myths and Truths About Poison Ivy, Poison Oak, and Poison Sumac

Myth #7: Once the eruption occurs, there are a variety of treatments that easily suppress the reaction and can be performed without visiting your physician. They vary from applying human urine to the site of the eruption to drenching the skin in gasoline.
Truth: For mild local reactions, it is generally necessary to apply potent topical steroids to the site for two to three weeks.