Poison Ivy and Poison Oak Symptoms & Causes

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What is poison ivy/poison oak?

There are three native American plants that, collectively, may be called poison ivy:

  • poison ivy
  • poison oak
  • poison sumac

These plants cause an allergic reaction in nearly 85 percent of the population. But to be allergic to poison ivy, your child must first be "sensitized" to the oils. This means that the next time your child has contact with the plant, a rash may occur.

What causes an allergic reaction?

The resin in the plants contains an oily substance called urushiol. Urushiol is easily transferred from the plants to other objects, including toys, garments and animals. This chemical can remain active for a year or longer. It is important to know that the oils can also be transferred from clothing and pets, and can be present in the smoke from a burning plant.

What are the symptoms of an allergic reaction to poison ivy/poison oak?

The reaction is usually contact dermatitis, which may occur several hours, days or even weeks after exposure. The dermatitis is characterized by a rash followed by bumps and blisters that itch. Sometimes, swelling occurs in the area of contact. Eventually, the blisters break, ooze and crust over.

Is poison ivy/poison oak contagious?

Poison ivy/poison oak can't be spread from person to person by touching the blisters, or from the fluid inside the blisters. It can be spread, however, if the oils remain on the skin, clothing or shoes. This is why washing your child's hands, clothes and shoes as soon as possible is very important.

Preventing poison ivy/poison oak:

  • Teach all family members to recognize the plants.
  • Make sure your child wears long pants and long sleeves when poison ivy or poison oak are in the vicinity.
  • Wash all clothes and shoes immediately after your child has been outside.
  • Make sure your child does not touch a pet that might have been in contact with a poisonous plant.
  • Wash your child's hands thoroughly.
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