poison plantThe itchy rash can drive your kids insane. But scratching only spreads the misery and makes it worse. That’s what you can expect when skin comes in contact with poison-packing plants like poison ivy, poison oak, or sumac. All three of them are found all around New Jersey, and simply brushing up against them can cause a nasty allergic reaction. 

Rash facts

The culprit behind the blistering rash is urushiol, an oil that produces a reaction in 85 percent of the population. Urushiol is found throughout the plants—on the leaves, stems, flowers, berries, and roots. Once skin comes into contact with the oil, a rash can develop within eight to 48 hours. 

The rash consists of small or large blisters that often appear as lines; they may be accompanied by itching, redness, swelling, or hives. Yellow crusts often form once the blisters burst. 

‘Leaves of three, beware of me’ is a phrase that may help identify and avoid the plants. 

What to do

If left untreated, a rash from poisonous plants can persist for weeks. Seek medical treatment if the rash is widespread or if it:

  • becomes infected
  • appears on the face or genitals
  • causes severe itching
  • makes it difficult for your child to breathe or swallow

 When the rash involves only a few areas, give your child Benadryl to reduce itching, or apply over-the-counter hydrocortisone cream. For larger areas, try Calamine lotion. With treatment, symptoms usually start to decrease in about 24 hours.

Act fast

If you think your child has touched one of the poison plants, take steps to avoid a reaction. “Shower or wash with soap and water within 10 to 15 minutes, or as quickly as possible,” says Babar Rao, MD, acting chair and associate professor of dermatology at the University of Medicine and Dentistry of New Jersey–Robert Wood Johnson Medical School. “If you don’t wash within an hour, it may not help,” he says. At that point, the oil has probably already penetrated the skin. 

Yet, even if you can’t avoid the rash completely, there’s a possibility washing may decrease the severity of the rash.

If the plant doesn’t come into direct contact with the skin, there’s still a risk the oil could contaminate other surfaces and cause a reaction. So be wary of oil that might be on clothing, shoes, jewelry, gardening tools, and sports equipment.

Dr. Rao suggests washing clothing in hot, sudsy water as soon as possible after coming in contact with the plants or the oil, and sealing any contaminated items that can’t be washed in a plastic bag. Touching someone with poison ivy or rubbing the rash cannot spread it. Once the rash appears, remind children not to scratch, since that can lead to a secondary infection. Keeping hands and fingernails clean will also help.

Poison ivy

This woody shrub climbs like a vine onto surrounding structures. It has three divided leaves with white, waxy berries on the stem. 

Poison oak 

Atlantic poison oak is a shrub that produces small, hairy, yellow-white berries. It grows up to three feet tall and glossy leaves change from bright green to red in summer. 


This moisture-loving shrub grows in standing water; each leaf has a row of paired leaflets. Black blotches may appear on the leaves, and the shrub has yellow-white berries. 

An Ounce of Prevention

  • Teach children to identify poison plants and caution against touching or brushing against them. Wash anything that has come into contact with the oil as soon as possible, including pets, toys, clothing, or shoes. Protective lotions, such as Ivy Block, are also available over the counter.
  • Wipe leather shoes and other items that can’t be laundered with rubbing alcohol and water. Remember to wear disposable gloves during the process.
  • Urishiol, the oil found in the plants, is very potent and is capable of producing a rash for years. The oil is active year round and touching even dead plants can cause a rash for as long as 1 to 5 years. 

What preventative measures do you take when it comes to avoiding poisonous plants?