Poison Ivy, Poison Sumac and Poison Oak

PoisonIvyWho can resist what summer brings us – beautiful weather for gardening, flowers blooming, tennis, fishing and playing outdoors for the children? Unfortunately, the nasty weeds-poison ivy, poison sumac and poison oak- grow alongside our beautiful flowers and can cause itching, discomfort and frustration to those allergic to them.

Poison ivy, poison sumac and poison oak are the group of plants that cause the most allergic reactions in the United States. Poison ivy rash is an allergic rash (dermatitis) caused by contact with an oil called urushiol, found in the sap of these plants. It is a colorless oil that oozes from any cut or crushed part of the plant, including the roots, stems and leaves. After exposure to air, urushiol turns brownish-black, making it easier to spot.

Poison ivy can be contracted in the following ways:

  • Direct contact – by touching the sap of the toxic plant with your skin.
  • Indirect contact – by touching something to which sap has spread. The sap can stick to the fur of animals, to garden tools , sports equipment, family members’ clothes or to any objects that have come into contact with a crushed or broken plant.
  • Airborne– urushiol (sap) particles, such as from the smoke of burning plants, may come in contact with your skin. Avoid the burning plants. The smoke may cause severe systemic allergic reactions.

Once urushiol sap touches the skin, it begins to penetrate in minutes. In those who are sensitive, some of the reaction appears as a line or streak of rash, usually within 12 to 72 hours. Redness and swelling occur, often followed by blisters and severe itching. The average rash takes 10 days or longer to heal. More severe cases can take 20 to 25 days to run their course.

The rash can affect almost any part of your body. The rash does not spread, although it may seem to when it breaks out in new areas. Before blisters form, the rash is spread by urushiol on your hands, for instance, by scratching your nose or wiping your forehead. Scratching poison ivy blisters will not spread the rash. It is best, however, to avoid excessive scratching of your blisters, since your fingernails may carry bacteria that could cause an infection.

If you think you’ve had a brush with poison ivy, poison oak or poison sumac, follow these simple steps:

  • Wash all exposed areas with cold running water as soon as possible.
  • Wash your clothing with a garden hose outside or in a washing machine with detergent. Because urushiol can remain active for months, wash camping, sporting, fishing or hunting gear that was in contact with the oil.
  • Relieve the itching of mild rashes by taking cool showers and applying over-the-counter preparations like calamine lotion or Burrow’s solution. Over-the-counter hydrocortisone creams are not often strong enough to have an effect on poison ivy rashes.
  • Seek medical help for moderate and severe cases, or if uncomfortable. I treat aggressively with systemic cortisone and topical medication (super-potent creams) when the itching prevents sleeping.

As you enjoy this beautiful summer season, be on the lookout for poison ivy plants.

John J. Jones, Jr. M.D.

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