FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

"THE URUSHIOL PLAGUE" ANOTHER NAME FOR A COMMON SUMMER PROBLEM

Question: I get poison ivy every summer. I've already had it this year, and it isn't even officially summer, yet! I try hard to avoid the plant when I'm outside, but I still get it. What else can I do to avoid it and what should I do when I do get it?

Answer: Poison ivy and its close relatives, poison oak and poison sumac, have the potential to cause itchy blisters in about 85 percent of those who are exposed it. This rash is known medically as allergic contact dermatitis, but most people simply call the condition "poison ivy."

The body's reaction to the chemical urushiol found within poison ivy's leaves, stems and roots is what actually produces the rash. In order for this chemical to get on your skin and produce a rash, the poison ivy plant must be broken. This is the reason that an allergic person can sometimes brush up against a healthy poison ivy plant and not break out.

Unfortunately, in many cases it's hard to tell whether or not a plant has been broken, since very small breaks caused by insects or other minor damage to the plant will let the urushiol onto the plant's surface. Urushiol is sticky so it can also be carried on the fur of animals, garden tools, golf balls or anything else that comes in contact with a broken plant. Touching these objects will transfer the offending chemical to your skin. Perhaps this is how you get poison ivy despite your best efforts to avoid the plant.

Once the chemical comes in contact with the skin, it begins to penetrate within minutes, but it takes from 12 hours to several days for the "poison ivy" to appear. First there is itching, redness and swelling, followed by blisters.

Contrary to myth, poison ivy can't be spread by touching the oozing liquid in the blisters!!! This liquid is not urushiol, but your body's own fluid produced as part of its reaction to urushiol. But as you know, poison ivy can be spread. If the victim gets urushiol on his or her hands, touching another part of the body or another person's body --can transfer the chemical to that area. That's the reason poison ivy tends to turn up all over the body, even though the plants generally only come in contact with the exposed areas of the skin.

The area which has the greatest exposure to the urushiol will usually break out first. Areas which have thick skin or less urushiol on them will then break out a day or two later, giving the impression that the poison ivy was spread from the first group of blisters.

If you suspect that you have been in contact with poison ivy or one of its cousins, the first thing to do is to thoroughly wash with soap and water. Any clothing that has come in contact with the sticky sap should also be washed promptly. Handle the clothes carefully, preferably with gloves, to prevent any more skin contact with the sap. If more than 20 minutes have elapsed since the exposure, washing may not prevent the initial rash, but it can prevent you from spreading it further.

Question: What's the best treatment for poison ivy?

Answer: There is no way to cure poison ivy once it develops, but it can be treated to lessen the discomfort. Mild cases may require no more than wet compresses or soaking in cold water to relieve the itching. But please don't use the old remedy of household bleach. I see quite a few individuals each year with severe skin irritation caused by this ineffective home remedy.

There are several non-prescription medications on the market that can dry up blisters and help relieve itching. Your physician or pharmacist can recommend one for you. None of the over-the-counter products should be used for more than seven days, and some should not be used on large parts of the body or on young children (read the instructions on the package).

Severe cases of poison ivy should be treated by a physician who may prescribe a few days of corticosteroids or other drugs to relieve the swelling, blisters and itching.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.