With summer upon us, parents are itching to ask me questions about poison ivy, and I certainly want to leave no leaf unturned when it comes to providing information on this common problem.

First the saying “leaves of three, let them be” is quite true. It is only when the leaves, roots, stems, or twigs are damaged or torn that the oil from this plant is released, causing an allergic reaction in 70% of the population. Within 4 hours to 4 days, red, itchy patches or blisters will appear wherever the oil is deposited on the skin

So, the name of the game is to wash your child thoroughly with soap and water as soon as you suspect they have been exposed to poison ivy. A shower with vigorous scrubbing is far better than a gentle washcloth, which can spread the oil.

And don’t just wash your child, but wash the clothes, shoes, toys, garden tools and even the towel used after the shower or the oil will be re-deposited onto your child and maybe even onto you. In addition, the family pet might be carrying the oil home from the woods so it might need a good hosing down as well if it’s been out and about in the woods during the day.

Once the oil has been removed, your child is no longer contagious. Even if blisters with fluid form, those blisters do not contain the oil, and thus are not contagious even if they look like they should be. Scratching affected areas will not make the rash spread if there is no oil on the skin, but it can lead to the rash becoming infected.

That’s why treatment is directed at helping reduce the itch and ease the suffering while the allergic reaction diminishes and eventually stops. Cool compresses with drying agents such as in calamine lotion or brown laundry soap or even oatmeal baths will sooth the itch. An oral anti-histamine medication available over the counter may also help. If the rash involves the eyes or spreads all over the body, then a brief course of steroids may be needed to decrease the inflammation.

When should you talk to your child’s doctor?

• If the rash involves the face or genitals
• If it is getting worse despite the home treatments I have recommended
• If the skin looks infected and you detect warmth, swelling, or pus
• If the rash is painful

Your child’s doctor can determine if treatment with steroids is needed to quiet down the inflammation, or if an antibiotic is needed to deal with an infected rash as a result of your child’s adventure with poison ivy.

Hopefully tips like this will do more than scratch the surface of your child’s skin when it comes to dealing with poison ivy.

Lewis First, M.D., is chief of Pediatrics at Vermont Children’s Hospital at the University of Vermont Medical Center and chair of the Department of Pediatrics at the Larner College of Medicine at UVM. You can also catch “First with Kids” weekly on WOKO 98.9FM and on WCAX-TV Channel 3. Visit the First with Kids video archives.


Lewis First, MD, is chief of Pediatrics at The University of Vermont Children’s Hospital and chair of the Department of Pediatrics at the Robert Larner, M.D. College of Medicine at the University of Vermont.

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