Bug of the Month: Poison Ivy, Oak or Sumac

Common and Technical Names:

Poison Ivy: Toxicodendron rydbergii

Poison Oak: Toxicodendron diversilobum

Poison Sumac: Toxicodendron vernix

Plant Identification: see this link: Cornell Poisonous Plants Information Database)

What it is:
Allergic reaction to urushiol oil from the poison ivy/oak/sumac leaves. The rhyme “leave three let them be!” can help kids remember to avoid clusters of three leaves together. 85% of kids can have allergic reactions to the oil.

Exposure Issues:

  • Plants: poison ivy, oak and sumac leaves
  • Non-plants: oil on toys and shoes that had been in contact previously with the oil; the oil can actually remain active for 1 year!

Typical Ages for Illness: any age in a susceptible person, someone who is sensitive to the oil

Typical Symptoms:rash and itching in the areas of skin in contact with the oil. This can be from direct contact with the plan or by fingers who touch the oil on the skin

Seasonal Issues:The plants are perennial but have different appearances as the seasons progress. See KidsHealth for great pictures of poison ivy through the seasons.

Incubation Period: rash typically starts 1-2 days after exposure to the plant oil

Diagnosis: by the distinctive appearance of the rash which has a bubbly look. For a typical appearance of the rash click here.

Symptom Duration:the rash can take 2 weeks to clear. It is not contagious.


Symptomatic! Stop the itch!!!!

  • over the counter products such as calamine lotion
  • oatmeal baths and lotions: Aveeno is the name brand to look for
  • antihistamines such as benadryl or claritin
  • 1% hydrocortisone cream to small areas 2 times a day but do not use to large areas of the body or the face, or more frequently, without consulting your pediatrician
  • local cold compresses

If these simple measures do not work and your child is very uncomfortable, call your pediatrician for further advice.

Exposure Prevention:

  • Teach your children to recognize the poison ivy plant.
  • Wear long pants, long sleeves, gloves and boots when in suspect areas.
  • Use barrier creams such as Ivy Block.
  • Remove plants if necessary (this should be done with caution—do not burn the plants since inhaling the smoke can lead to very serious reactions).

Call Your Pediatrician if your child has:

  • wide spread areas of rash
  • rash near the eyes or mouth
  • any areas or the rash that appear infected, have frank push or appear red or angry looking, are tender, have red streaking, or the child has a fever

Internet Resources For Parents

American Academy of Dermatology Poison Ivy/Oak/Sumac Page

Children’s Hospital Boston Information on Poison Ivy and After Care Instructions

Lucile Packard Children’s Hospital

Internet Resources for Kids and Teens

American Academy of Dermatology Pesky Poisonous Plants Page

KidsHealth Information for Kids on Poison Ivy

KidsHealth info for Teens on Poison Ivy

online pharmacy www.drugstoremg.com