Poison Ivy and Poison Oak Treatment


There are some lucky people who don’t get poison ivy or oak. If you’re like me, you do. Here are some poison plant pointers:

Ivy block cream prevents poison ivy or oak, but only if it is applied 15 minutes before exposure. It doesn’t work after you’ve been exposed.

The intensely itchy, sometimes frighteningly-bubbly rash is an allergic reaction to oil, urishiol, found on poison ivy, oak and sumac plants.

You can wash off the oil with soap and water. Do not use laundry detergent, alcohol, or expensive poison ivy soap — any ordinary bar of soap will wash off the oil. However, the oil is quickly absorbed into your skin, like olive oil into nice piece of Italian bread, so time is of the essence. Once the oil is absorbed in your skin, you cannot get it out no matter what you use.

  • You can wash off 50% of the oil within 10 minutes
  • You can wash off 10% of the oil within in 30 minutes
  • After 1 hour, no amount of washing will make any difference. Nothing will prevent the soon to be rash.

Whatever you do, don’t touch your groin in the first hour or so. You could end up in the hospital; I’ve seen it.

After one hour, you cannot spread poison ivy to someone else. Scratching or breaking the water blisters does not spread the poison ivy or the rash.

The rash lasts for 2 weeks, sometimes less if it is not severe. No cream or treatment, however expensive, can shorten the duration. The rash must run its course.

Once your arms and face turn into wet tapioca pudding, use a drying astringent like Domboro soaks to dry it out.

Once the blistering dries up, apply a topical steroid like hydrocortisone 1% cream or anti-itching lotions like topical Calamine or Benadryl. Cool baths with collodial oatmeal will also help. Super hot showers will relieve the itching, but only temporarily, and in the end, only makes it worse.

If you have a severe case of poison ivy, defined by your mother doesn’t recognize you or you are unable to sit, stand, or lie down, then see a dermatologist for prescription drugs to help.

Photo: Jim Frazier (flickr)

Post by Dr. Benabio, copyright The Derm Blog 2009.

9 thoughts on “Poison Ivy and Poison Oak Treatment”

  1. I’ve had very good luck with Ivy Block used to prevent the rash. I’ve also heard that sun block cream and aerosol deodorant sprayed on the skin beforehand will help prevent the rash, but I’ve never tried it.

    Tecnu can definitely help. You rub it on the skin after exposure, and even an hour or longer after it can help keep the rash manageable. Several years ago we had to special order it, but now you can find small bottles in most pharmacies.

  2. Stumbled across your wife’s blog (Limoncello..yum!) Saw her mention of your blog, and since (in addition to being a hungry New England Italian gal) I’m a wound care nurse, I *had* to visit.

    Your poison ivy info is timely and helpful! In the past, I have used Tecnu immediately after exposure, followed by an OTC compound of 1:1:1 Dibucaine, Benadryl and cortisone ointment to mitigate discomfort and itching.

    Recently, I discovered a new product, ReLeaf Urushiol Scrub, which I am trialling with plans to write a (not from a professional angle – just as an everyday user) review for the new company. So far I am *very* impressed…

    You’ve been bookmarked for future reference! :o)

  3. I forgot to add that it’s very important to protect yourself even if you don’t *seem* react to poison ivy. On my first encounter with it (since childhood) two seasons ago, I showed no reaction whatsoever, so I boldly (stupidly) pulled it barehanded for my highly allergic husband.

    Like other allergic reactions, it can develop and/or intensify over time. The following season I repeated my blind arrogance and was rewarded with a lovely bloom of moist nastiness on my bilateral forearms, and anywhere else I touched myself. Ick…

    I’ve since learned to protect myself, before and after playing in it, as my reaction seems to intensify with each exposure. Lesson learned…

  4. Lizzard, I just tried some of the new product, Releaf Stuff as well and am very impressed. I got a case of poison ivy rash in my backyard a couple days back and I found the Releaf Stuff at a local nursery store and it has worked well. Their packaging gives a webpage at http://www.dontforgetthestuff.com and an Amazon store. Releaf Stuff scrubs like Zanfel but something in it keeps the skin from itching afterwards for quite a while.

    I used Zanfel in the past but this was cheaper and felt better afterwards. It also had twice as much in the container than Zanfel, and for a lower price.

  5. I’ve tried so many of the different remedies suggested but the only one that seems to truly work for me is calamine with phenol. If i use just the regular calamine it helps a little but not for long at all. I have neve tried zanfel but i hear it does work as well. I just have a hard time spending that much for a remedy at home. I might as well go to the doctor for a medrol pack which does work wonders.

  6. I’ve found that the best thing for the itch is the hottest water I can stand in the shower. I have to take 2 showers a day when I have poison oak, or ivy. Nothing seems to stop the itch better then the hot water.
    I hold the infected area as long as I can under the hot water until the itch dissipates. I have to turn my hot water heater up when I get the poison because it has to be very hot. After my shower it really doesn’t matter what I put on. Be careful with children!

  7. I live in Northern California, have a dog, and am highly allergic to Poison Oak. I recently discovered that a hydrosol spray of Bay Laurel works magically to combat the itching and greatly speeds recovery. As a result, I’m no longer reliant on topical steroids, thank goodness! I highly recommend Allstar Organics Bay Laurel hydrosol. It has changed my life. It can be purchased on their website. Allstarorganics.com.

Comments are closed.