Published: October 29, 2008 11:52 am         

Poison oak, ivy doesn’t have to be green to infect you

Health Watch by Rebecca J. Cripps

The North Jefferson News



This is the time of year for the leaves to start falling and flowers to start dying.

It is inevitable that we will get out in our yards to rake the leaves and clean out flower beds. During all this activity, we may run across poison ivy or oak.

A common misconception is that you can only “get it” when the plant looks green and healthy. In fact, you can get poison ivy from handling dead leaves of the vine.

Uroshiol is the toxin that lives in the vines of poison ivy, oak and sumac. Many plants containing uroshiol have three leaves, allowing the saying “Leaves of three, let it be!”.

However, not all plants with uroshiol have only 3 leaves. Therefore, it is important to review the ways to prevent and treat poison ivy.

There are ways to prevent getting this rash even after touching the plant. There are also ways to treat poison ivy if you do get it.

To prevent exposure to poison ivy and oak, wear gloves, long sleeves, pants, shoes and socks. There is a product called Ivy Block lotion which is used to prevent the rash.

However, it must be applied to clean, dry skin 15 minutes before the risk of exposure. It also should be reapplied every four hours to continue protection.

If no precautions are taken and exposure occurs, wash the area with soap and cool water for 10 minutes to remove the uroshiol from the skin.

This is the best way to prevent getting the rash once the plant has been touched. Technu Outdoor Skin Cleanser can also be used to prevent a rash from poison ivy. It removes the uroshiol from the skin before the rash develops. It must be used within one hour of contact with the plant. However, it does not seem to have any benefit greater than mild soap and water.

If these protective measures are not used or not beneficial, there are many over-the-counter products sold which treat poison ivy/oak/sumac.

The best over-the-counter treatment has been proven to be hydrocortisone, a topical steroid. It should be applied to the affected area three to four times a day. Other treatments include topical analgesics like phenol, camphor or menthol which help to relieve the pain and itching caused by the rash.

Calamine, witch hazel, zinc oxide, and zinc acetate can be used to promote healing and relieve inflammation. Caladryl is a product containing calamine and diphenhydramine, a topical antihistamine. It has been proven to be less effective than calamine lotion alone.

Topical antihistamines have been proven to have limited effect for the rash. Oral antihistamines like Benadryl (diphenhydramine) and Chlor-Trimetron (chlorpheniramine) can reduce the itching caused by the rash, but may be limited by their side effect of drowsiness.

Topical anesthetics like benzocaine or pramoxine are not recommended for poison ivy. They have been proven to cause skin to be more sensitive which could cause the itch to worsen.

The following circumstances could require treatment from a physician or prescription medications:

• If the patient is less than 2 years of age

• If rash lasts more than 2 weeks

• If more than 25 percent of body is affected by rash

• If swelling of the body or extremities occurs

• If involvement of the genitalia, eyes, ears, or nose occurs

In conclusion, the best ways to prevent this rash is to be cautious while participating in outdoor activities. Remember that even dead poison ivy, oak or sumac leaves can contain uroshiol which causes the rash. If exposure does occur, immediately wash with cool water and mild soap.

If the rash occurs, follow the treatment recommendations above and resist scratching the rash as much as possible.

Itching should be reduced after a few days and should begin to disappear after a week. As always, call a pharmacist or physician with any questions or concerns.

Rebecca J. Cripps is a student at Samford University’s McWhorter School of Pharmacy and a PharmD intern at The Pharmacy in Mt. Olive. The Pharmacy can be reached at 631-1201.