Poison Ivy

If you've ever had a run-in with poison ivy, poison oak, or poison sumac, you know the results: an itchy, blistering rash. The best way to prevent it is to avoid the plants.

Know the enemy

Poison ivy can be found in most parts of the country. Poison oak grows in the eastern states and along the West Coast. Poison sumac is found mainly in swampy areas in the Southeast. Although these plants look different, the damage they do is similar. An old saying to help people avoid these plants is "Leaves of three, let the be." That's good advice, but it doesn't go far enough. The leaves also may grow 5, 7, 9, 11, or 13 to a stem.

Poison ivy comes in many varieties. It's common in wooded areas and also is found near lakes and streams. Poison ivy often grows as a vine, but it can also be shrub. The leaves are often the first to turn color-red-in the fall. In the spring the plant has yellow or green flowers or white berries.

Poison oak takes two forms. In the East and South, it grows as a low shrub; along the Pacific Coast, it may be a tall shrub a high-climbing vine. The notched leave resemble those of the common white oak tree. The yellow berries grow in cluster. Poison sumac favors boggy areas. The tall shrub has 7 to 13 smooth-edge leaflets on each stem. The berries are pale yellow.

The best advice is to learn what the problem plants in your area look like. Also, avoid any plant with black spots. Those are marks of urushiol, the substance in the sap that causes the rash. All parts of these plants contain the sap - not just the leaves but also the vines, stems, roots, flowers, and berries. Do not touch any part of the plant. The sap can last throughout the winter, so choose your firewood carefully!

How to protect yourself

Whenever you are planning to be in an area where poison ivy, oak, or sumac grows, take some protective steps:

What to do if you break out

If the itch is bad, your doctor will give you medication. Follow your doctor's instructions for taking the medicine. Most people find cool, moist compresses helpful. Oatmeal soaks (Aveeno) also bring relief. A lotion like calamine is soothing, but don't use products like Benadryl on your skin (you can use Benadryl pills to reduce the itch), which contains a drug that can make the rash worse. Try not to scratch, not matter how much you itch. Scratching can break the skin and lead to infection. You can't spread the rash by scratching, however, unless you have the sap under your nails.

Don't worry about giving the rash to your family. It is not contagious. The only way to get a reaction to poison ivy is to come into direct contact with the sap. If you don't know how you got the rash, do some investigating. Until you find the source of the sap and remove it, you risk more outbreaks. Some possible sources are: