About Poison Oak

Poison oak, the dreaded cousin of poison ivy and poison sumac, is found throughout the United States and can cause an allergic reaction in most people that come in contact with it. The rash that can occur after contact with poison oak is similar to the rashes created by poison ivy and poison sumac because all three of these plants contain the same rash-causing substance, urushiol. It is imperative to learn how to identify poison oak in order to avoid contact with it, and to know what to do if exposure to poison oak has already occurred.

Identification

• Poison oak is most commonly found as a shrub, though it can also appear as a vine in areas along the west coast of the United States. The leaves of poison oak resemble the leaves of oak trees, occur in threes and are usually shiny and green. There are often small, green flowers or clusters of yellow berries on poison oak bushes. The stems of the poison oak bush is usually thick and sturdy in appearance.

Features

• Over 80 percent of people are allergic to the urushiol oil that is present in the leaves of poison oak, causing an itchy rash in all areas of contact. Redness on the skin will usually occur within 48 hours of exposure to poison oak, followed shortly thereafter by pus-filled itchy blisters. While scratching, these blisters will not spread the poison oak rash to other parts of the body, as commonly believed; however, it can cause a secondary bacterial infection in the rash site and should be discouraged. The rash caused by poison oak will normally clear up in two to three weeks, but it is extremely itchy and uncomfortable, especially when present on large areas of the body.

Effects

• While there is nothing that can clear up the poison oak rash, there are several ways to help dry out the poison oak blisters and relieve the itching they cause. Frequent bathing in cool water and cool compresses are effective in minimizing the itchiness of the rash, but warm baths should be avoided because they can irritate the poison oak rash further. Oatmeal baths are also proven to provide relief from itchiness. After bathing, applying calamine lotion to the poison oak rash will help to reduce the urge to itch the rash. Oral antihistamines, like Benadryl, are also effective in relieving the itchiness of the poison oak rash, but they do cause drowsiness.

Warning

• The urushiol oil of the poison oak leaves is highly potent and can remain active for more than a year. Any clothing that comes into contact with the poison oak bush should immediately be washed to avoid spreading the oil and creating the rash at a later date. This is also true for any pets or items in the yard that may have come into contact with the poison oak.
  If the poison oak spreads to the face or does not show signs of clearing up after two to three weeks, a physician should be seen to examine the rash. If the itchiness of the poison oak rash is unbearable, particularly when it covers large areas of the body, a physician can prescribe certain steroids to help relieve the discomfort.

Prevention/Solution

• Learning to identify the poison oak bush or vine is the first step in avoiding contact with poison oak and the rash it can cause. Keeping your yard well maintained and uprooting anything that looks like poison oak (with gloves that are washed immediately after contact) can help prevent exposure to the oil it creates and its subsequent rash. If contact with poison oak is suspected, immediately washing the area of contact with soap can sometimes wash off the urushiol, preventing the poison oak rash from occurring or at least from spreading to other areas of the body.