Summer is a wonderful time to enjoy the great outdoors.  However, you must be careful while you commune with nature.  Potential hazards include both flora and fauna.  Among the flora causing hazards are poison ivy, poison oak, and poison sumac.

Ten to fifty million people each year develop allergic reactions to these plants, which are found all over the continental United States.  The reaction is caused by an allergic response to urucial, a colorless oil found in the leaves, stems, and roots.  The oil is spread by one of three mechanisms:

1. Direct contact:  touching the urucial oil
2. Indirect contact:  touching something that has the oil on it, such as animal fur, camping or sporting equipment, or clothing
3. Airborne:  urucial particles in the air created by burning the plant

I recall treating one child with poison ivy in the fall who then had it recur in the spring after no obvious exposure.  Upon further questioning, we learned the jacket he wore in the fall while in the woods was left hanging in the garage over the winter.  When he put it on again in March, the oil was apparently still present and the child had a recurrence of the poison ivy.  Carefully washing the jacket prevented any new episodes.

If contact with poison ivy has occurred, immediately wash the exposed area with water from a hose or running stream as the oil can start to penetrate the skin within minutes.  Next, wash with soap and water within 30 minutes.  If the urucial oil gets on clothing, wash immediately and take care not to put the clothing on furniture or rugs as the oil can be transferred to these other surfaces.

Myths abound regarding poison ivy, oak, and sumac including:

1. The rash is contagious:  FALSE.  The rash is an allergic reaction to the oil.  Only the oil is “catchy," meaning it passes from person to person via direct contact.
2. The rash keeps spreading over time all over your body:  FALSE.  If the oil is on your hand, you can put it anywhere on your body by touch.  The rash may not appear simultaneously because differences in skin thickness affect the rate of absorption of the oil.  For example, a rash will show up sooner on your face than on your legs.
3. Once allergic always allergic:  FALSE.  An individual can have varying degrees of sensitivity from year to year.  One can be highly allergic as a child yet have a mild reaction as an adult.
4. Dead plants are less toxic:  FALSE.  The oil can remain active for many years, even if the rest of the plant is dead.

The rash of poison ivy begins with itching, redness, and swelling.  Most areas blister and eventually ooze a clear fluid prior to scabbing over.  The entire reaction can take 10 or more days to resolve.  So what should you do in the meantime?  Try not to scratch, as bacteria under the fingernails can potentially cause infection at the site of the rash.  Calamine lotion and tepid baths can help.  Severe or extensive swelling may require a visit to your primary care doctor who can provide treatment with prescription-strength corticosteroid creams or an oral medication.

The best advice is to teach your children at an early age to recognize poison ivy, oak, and sumac; to watch where they walk in the woods; and to be careful about what they touch.  With these precautions in mind, the whole family can relax and enjoy the outdoors and all that nature has to offer.

Written by:
Linda Roochvarg, MD
Board-certified Pediatrician

 

 
 
 

For more information, visit:
www.aad.org   (the website of the American Academy of Dermatology)
www.webmd.com