Poison Oak

For all of my blogging over the years, poison oak has been one of the subjects that I have had on my “to do” list but haven’t sat down and pounded it out until now. This week I have gotten multiple calls about poor little patients with probable poison oak. Several of them most likely got it from Glen Park. The symptoms start with a small itchy rash that then spreads over the next several days into weepy, nasty blisters. The rash can begin within a few hours of contact, but keep in mind that it might not actually show up for several days. It usually takes about 2 weeks to clear up. At least three out of four  people coming into contact with the plant will end up with a problem, but some folks are much more sensitive than others. As with most allergies, the reaction tends to get worse with each exposure. The substance that the skin is reacting to is an oil called urushiol (ooh-roo-she-all). Urushiol is found in all parts of the poison ivy, oak and sumac plants. When urushiol gets on the skin it binds to the skin within 10-20 minutes. At that point the urushiol becomes extremely difficult, if not impossible, to get off the skin with soap and water. The oil can linger under the fingernails. The rash itself is NOT contagious, but if you still have oil under the nails, it can be spread from the scratching. The key is to wash any possible areas that came in contact with the plant immediately after any possible contact. If you are spending time outdoors please keep a product called Tecnu in your backpack. Simply apply Tecnu to dry skin, rub vigorously for two minutes, and rinse with cool water or wipe off with a cloth. When used within 2-8 hours after exposure to poison oak, ivy or sumac, Tecnu can remove urushiol oil before the rash begins. Once a poison plant rash has started, washing with Tecnu is still somewhat useful because it helps remove any free oil on the skin allowing the natural healing process to begin without the possible spreading of poison ivy or oak (re-contamination). If you don’t have that, you can use rubbing alcohol. Some folks use dishwashing detergent. Dawn is especially good at removing oil. Avoid using warm water because that will enhance the penetration of the oil Poison ivy and oak oil can also spread from contaminated clothing, shoes (don't ignore the laces), gloves, tools and pets. Since urushiol oil does not evaporate, it can remain on these items for months or even years at a time. Gardening tools, sports equipment, clothes and pets are all possible sources. Get in the habit of washing any suspicious objects before storing them so that they don’t cause trouble later on. All exposed clothes should be removed and soaked in a pan with Tecnu prior to being washed. Pets are actually a pretty common culprit for spreading poison oak. If you have a dog, try to keep them on the paths if you are out hiking; dogs can get the oil on their fur and it will transfer to humans when you snuggle them. Pets can be wiped off with tecnu prior to being washed off with a pet shampoo. If it is too late and you or your child has poison oak, it usually takes a couple of weeks until it clears. For a mild case, taking Zyrtec or Benedryl, oatmeal baths and topical steroid creams can give some relief. There is also a good product  called Domeboro gel. Dr Schwanke strongly prefers Zyrtec to Benedryl as an oral antihistamine because it lasts longer and won't "turn your kid into a zombie". Of course if you are looking for a little Zombie at night, you might do Zyrtec in the morning and Benedryl for the night time dose. If the rash has spread to the face or genitals (with boys, that is pretty much a given) you may need a course of steroids. Dr. Fast, my go to allergist, strongly recommends hitting any poison oak  hard and fast with oral steroids. Dr. Hurd has a more cautious  approach with the steroids. Some kids get a bit hyper from them, so if the rash is mild enough, she would rather stick with the topical symptomatic relief remedies. My daughter Alana was on a course of steroids once and that week she ended up sewing several pairs of pajamas because she didn't seem to know what else to do with her body. Steroids can make you feel weird but a short term course is not dangerous. A less than 10 day course does not need to be weaned down although several doctors in our office all have different ways of prescribing the steroids. It is a good idea to learn how to recognize poison oak even though the plant can spread the oil when there are no leaves, so nature isn’t making it all that easy to avoid. Most of the time there are three leaves. At some points there may be little flowers and berries. During some seasons the leaves turn red. If there are thorns it isn’t poison oak (of course now you will be calling me about thorn issues. Stay on the path!) It is rampant all over the Bay Area, but if you are heading up to the mountains you can take some comfort in in knowing that poison oak does not grow above 4300 feet. If you are in the vicinity where  Poison oak is being burned, be careful, burning can cause irritated airways, eyes...etc. Know your area. Many places will have warning signs posted that there is poison oak in the area. Be prepared. Stay on the paths. Wash of any areas of skin that have had potential exposure. Most importantly, make sure to scrub your hands especially under the nails, when coming in from a hike.

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