Or could it be poison oak or poison sumac? This is how to tell, plus what you'll need to do to make the itching stop.
poison oak rash
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If your child develops an itchy, blistering rash that appears as lines or streaks on the body, she's most likely come in contact with a poison ivy, poison oak (that's what's pictured here), or poison sumac plant. All three of these plants contain urushiol, the oil that triggers the rash. Approximately 85 percent of us are sensitive -- meaning allergic -- to this oil and develop the rash, formally known as allergic contact dermatitis. The rash initially shows up as streaks -- a direct result of the leaves brushing up against the body -- but can also appear as patches, if the oil is then spread to other parts of the body.

Symptoms of Poison Ivy, Poison Oak, and Poison Sumac

Because urushiol is the common irritant, all three poisonous plants bring on the same symptoms. "If this is a child's first exposure to the plant, it may take more than a week for the rash to appear," says Parents advisor Jody A. Levine, M.D., director of dermatology at Plastic Surgery & Dermatology of NYC. Kids who have been exposed to the plant before will likely develop symptoms much faster. "Once it touches the skin, the rash can develop anywhere from eight hours to two days later," says Dr. Levine. "And it can range from general redness to hives to fluid-filled blisters." Once the rash appears, it can then continue to develop over several days, with new blistering areas emerging. "This is just the rash displaying itself -- it's not the result of it spreading from one blistering area to another," says Parents advisor Lawrence F. Eichenfield, M.D., professor of pediatrics and dermatology at University of California, San Diego and chief of pediatric and adolescent dermatology at Rady Children's Hospital. The places on the body that came in contact with the most oil will display the rash first, followed by areas that have lesser amounts.

The expected healing time can widely vary, too. "The course of the rash can be days to several weeks," says Dr. Eichenfield. "It depends on how much exposure and how intense the allergic response to the plant is." But one to three weeks is typical.

At-Home Treatment Versus Doctor Care

If you're certain your child has been exposed to a poisonous plant and the rash only affects one area, it's possible to treat him at home without calling the pediatrician first. The affected area should be washed immediately after contact, along with your child's clothes, toys, and anything else that might have had contact with the plant. And the best way to treat the itch is to appropriately treat the rash. "Wet compresses, cool baths and calamine lotion can all help reduce the itching," says Dr. Levine.

If you're unsure of the diagnosis or the extent of contact, call your pediatrician. "And if there's tremendous swelling, uncontrollable itching, or your child is unable to function normally, it's time to see a dermatologist," says Dr. Eichenfield. This may even warrant a trip to the emergency room, especially if your child is having trouble breathing or swallowing, or if the rash covers most of the body. In more severe cases, a doctor might prescribe oral or topical corticosteroids, or topical anti-inflammatory medicine to help relieve your child's symptoms.

Spreading Poison Ivy, Poison Oak, or Poison Sumac

Believe it or not, a child with poison ivy, oak, or sumac is not contagious. Another person can't contract the rash by touching him, unless your child still has traces of urushiol on his skin. With that in mind, "it is totally possible to contract poison ivy, oak, or sumac without the skin actually touching the plant," says Dr. Levine. "The irritant that causes the rash can be transferred through clothing, shoes, tools, toys, and animal fur." Pay particular attention to pets since they may have come in contact with a poisonous plant and be carrying the oil on their fur without showing any signs of irritation. Pets aren't immune to the affects of the poison and can have an allergic reaction to urushiol. However, "since pets have fur, the oil usually doesn't make it to the pet's skin," says Dr. Eichenfield. If you know your pet has been exposed to the plant, bathe the animal and be sure to wear rubber gloves. And use a barrier cream, such as a lotion containing bentoquatum (look for Ivy Block in drugstores), on any skin not protected by the gloves. Also use lots of cool water to bathe the pet.

Removal of Poisonous Plants

Should you find a poisonous plant in your yard, your best bet is to have it removed by a professional. Removal experts can pull up the plants from the roots and offer maintenance programs that help prevent the growth of new plants. There are herbicides that you can use to try and kill the plants but they run the risk of leaving some areas untreated, therefore inviting the plants to return. Plus, a chemical-free solution might be the safer option for treating areas frequented by kids. But just remember to never burn the plants. This can be incredibly dangerous since smoke inhalation from burning poison ivy, oak, or sumac plants can cause severe allergic respiratory problems.

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