Perils of Poisonous Plants; Should I Be Treated?

Summer is here. Yard work beckons. Kids go to camp. We take long hikes through forested areas. But just as you start to enjoy yourself ... Hey, what’s that itch?  

Rashes abound in summer. Treatments range from over-the-counter medications to grandma’s home remedy.  But how can you avoid rashes in the first place?  How do you prevent a rash from starting if you’ve been exposed? How is poison sap spread? What could a doctor offer?  Finally, when is the rash getting infected?  

Shown here is a common poisonous plant, poison ivy, of the genus Toxicodendrum, which includes poison oak and poison sumac. You may not notice such plants when you are exposed, because they are commonly camouflaged by other brush. These plants cause a condition called contact dermatitis, an allergic reaction caused by memory T cells of your body’s immune system reacting to the plant resin “urushiol.”  

Urushiol is sticky and can stay on tools, pets and shoes for months. Once you are exposed, your skin may swell and blister in response, usually in a streak-type distribution where the plant has brushed against it. The clear fluid (serum) inside the blisters is not contagious to you or anyone else. But the rash may continue to spread and new spots may form for days, typically because something in your environment still has the sticky plant sap on it. Big culprits are shoestrings. Wash your shoestrings and your sheets, preferably with hot water and bleach. As for yourself, you may try washing with one of the over-the-counter soaps designed for poison plants. Scrub vigorously in the shower. If used soon after an exposure, the soap may even prevent the rash.

If you are one of the unfortunates with an out-of-control rash, you may want to seek medical advice. Some tips on when to seek a doctor are as follows:

• If your rash hurts instead of itching, or oozes pus, it may not be poison plant related. Such rashes are infectious and dangerous. Urgency of this situation increases if you have a fever.

• You are at your wit’s end with itching. But be forewarned, the steroids doctors use for treatment of these rashes are not without side effects. You shouldn’t take them if you have high blood pressure, diabetes, Cushing’s syndrome, or a surgery planned, to name a few exclusions.

• If your rash doesn’t form streaks in areas of exposure, you may not have a rash related to poison plants. Although itchy rashes with no associated fever are a nuisance, they are rarely dangerous. They do warrant physician review, however, if you’ve started taking a new medicine recently. 

• Finally, if any rash is associated with shortness of breath, swelling in your face or mouth, or wheezing, you should get medical help immediately. Call 911.

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