Summertime Skin Irritants

Published on in CHOP News

Learn how to treat common summertime skin irritants, including Poison Ivy, Poison Oak, Poison Sumac and Jellyfish.

Poison Ivy, Poison Oak and Poison Sumac

Although poison ivy, poison oak and poison sumac are often thought of as summertime hazards, these plants are also commonly found throughout the fall season.

Poison ivy, poison oak and poison sumac are common causes of seasonal, allergic contact dermatitis (rash). It has been estimated that up to 70 percent of the U.S. population has an allergic reaction after an exposure to these plants. The reaction may range from mild, localized redness and itching to severe blister formation and swelling over the entire body. The severity of the symptoms depends on the patient's degree of sensitivity, the amount of contact with the offending material and the areas of skin involved.

The offending material in all species of poison ivy, poison oak and poison sumac is an oily resin known as urushiol. This oily resin is found in the leaves, stems, roots and berries of all of these plants. When this resin comes in contact with the skin or fingernails, it clings there and becomes tightly bound within minutes.

Contrary to popular belief, the fluid in blisters caused by poison ivy, oak and sumac does not spread the rash. It is the oily plant resin that is the culprit. The offending resin can remain active for long periods of time on contaminated clothing, shoes sports or hunting equipment, camping gear, garden and yard tools and even the family pet.

First aid

  • Do not scratch the rash. Cold, soapless showers or colloidal oatmeal baths (Aveeno) can soothe the itchy skin.
  • Oral antihistamine (Benadryl®) can help with severe itching and swelling. Remember, antihistamines may cause drowsiness. Use caution when operating cars, boats and machinery.
  • Topical hydrocortisone cream (Cortaid®) can control itching and dry skin.
  • For moderate to severe cases, consult your physician who may prescribe oral steroids or more potent steroid creams.


  • Learn to recognize poison ivy. Teach your children to recognize and avoid it.
  • Wear gloves, long sleeves and pants when working in the garden or when you will be in areas where poison ivy grows.
  • Wash clothes, sporting equipment and tools which have been used outdoors in hot water. Handle these items carefully.
  • A new product called Ivy Block™ is available in drug stores. We do not have experience with this product. However, the manufacturer claims that it is effective when used along with gloves, long-sleeves and pants.
  • Never attempt to destroy poisonous plants or shrubs in your backyard by burning them. Inhalation of the smoke produced by the burning of these plants can cause a life-threatening reaction.


A jellyfish's tentacles are loaded with small bee-like stingers that contain a toxin used to stun small water prey. This is why within four to 24 hours after a human is exposed to the stinger of a jellyfish, the affected skin can become painful, red and swollen and an itchy rash can appear.

With severe stings — when a lot of venom is injected into the skin or when a person is extremely allergic to the venom — weakness, dizziness, nausea, headache, muscle aches and spasms, and difficulty breathing can result. If severe symptoms occur, the victim should be seen by a physician or emergency room staff. If symptoms are mild, the following first aid advice may help:

  • Bathe the affected area in household vinegar (5 percent acetic acid) for 30 minutes. Vinegar will help inactivate the remaining toxin. Vinegar may be irritating, however, it will help in the long run.
  • A cold pack (ice in a towel) and a local anesthetic cream may reduce pain.
  • Topical hydrocortisone cream and/or an antihistamine may help to reduce further pain, swelling and inflammation.
  • Remember, antihistamines may cause drowsiness. Use caution when operating cars, boats and machinery.