Poison Oak: Identification and Treatment

What's the Difference Between Poison Oak and Poison Ivy?

By Samantha Caveny
June 24, 2019
poison-oak-identify-treat

Poison oak can be a harmful plant if you touch it, as its urushiol oil will cause a nasty rash.

California State University Channel Islands

“Leaves of three, let it be!” “Hairy vine, no friend of mine!” Learn how to spot poison oak, tell the difference between poison oak and poison ivy, and treat a poison oak rash. 

What is the Difference Between Poison Oak and Poison Ivy?

Poison oak is a relative of poison ivy. There are many similarities:

  • Both plants contain the same toxic resin, urushiol in all parts of the plant (toxic to humans but harmless to animals). 
  • Both plants have three leaflets, white flowers in spring, and can grow as a vine or a shrub.
  • Leaflets can range in size from the length of your thumb to the length of your hand.
  • Middle leaflet has a notably longer stem than the two side leaflets, though more obvious in poison ivy than poison oak.
  • Depending on the season, leaf color can range from green to orange and even a dark purplish-red.

But they are indeed different plants. In North America, there are two species of poison oak: Atlantic (Eastern) and Pacific (Western). 

Poison ivy (left) vs. poison oak (right)
Poison ivy (left) vs. poison oak (right)

How to Identify Poison Oak

  • Poison oak is a low-growing, upright shrub. It can grow to be about 3 feet tall, sometimes giving it the appearance of a vine. 
  • Leaf shape resembles an oak leaf (hence the name, poison oak), but it’s not a member of the oak family.
  • Leaflets are duller green than poison ivy and usually more distinctly lobed or toothed.
  • Leaflets have hairs on both sides, unlike poison ivy.
  • Poison oak tends to grow at elevations between sea level and 5,000 feet.
  • While the fruit of poison ivy is the color of pearls, poison oak fruit (called “drupes”) has a tan color.

At the end of the day, just remember: Leaves of three, let it be. In other words, if you see a plant with clusters of three leaves, don’t touch it!

poison-oak-fruit-identify.jpgpoison-oak-cluster_0.jpg
Left: Poison Oak can be red in the fall, and its berries are tan when mature. Right: Poison Oak leaflets showing coloration.

Poison Oak Symptoms

Symptoms of poison oak include itchy red rashes that can resemble burns, swelling, and even blistering.

Symptoms can take 24-48 hours or even up to a week to show up, particularly if its your first exposure! 

Poison oak, like poison ivy, contains urushiol. This oily substance is what causes a poison oak rash, and it can be almost impossible to avoid. Upon contact with your body, urushiol immediately forms a chemical bond to the skin and causes an almost unstoppable allergic reaction. Urushiol will stay on clothes, pets, or other materials for months, and its potency lasts. This means that you could even get poison oak without going anywhere near it. 

The urushiol resin can cause harsher reactions for those who have been exposed to it before. Sensitivity to urushiol might decrease if you do not come into contact with it until later in life. Only about 15 percent of people are resistant to urushiol, so don’t feel safe around poison oak unless you are absolutely sure you are resistant. You also may become sensitive with repeated exposure, so your resistance might be short-lived.

Danger: Smoke inhalation from burning poison oak can send you straight to the emergency room. Avoid burning this plant (and poison ivy)!

Poison Oak Treatment

Your best chance at avoiding a reaction is to treat poison oak within 10 minutes of contact.

Urushiol is not water-soluble! Use strong soaps (like dish soap) and wash with cold water to keep the oils from spreading. Cleanse the area of contact within the first ten minutes, then rinse off with cold water. As urushiol can remain active for years, you’ll want to wash any clothes, items, or furniture that may have come into contact with the invisible oily residue.

If you don’t catch the exposure immediately, treat the resulting itchy rash and blisters topically with calamine lotion, baking soda pastes, aloe vera, and a number of commercial products.  If you don’t mind mixing breakfast and skin care, one tried-and-true remedy for itchy skin is oatmeal.  Since poison oak rash is the same as the poison ivy rash, see more remedies on our poison ivy page. If poison oak is extremely serious, speak to your doctor about a prescription.

Of course, the best remedy is always prevention; study our photos so you can recognize poison oak.

Have you ever had a run-in with poison oak? Tell us about it in the comments below!

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poison oak

I've had poison oak rashes a few times. I'm very sensitive to it, and it sets in fast, like within 30 min or so... Not fun! When I'm out hiking in poison oak country, I carry a bottle of rubbing alcohol along with Tecnu and a bar of soap. Rubbing alcohol works great -- just soak a bandana in it, and then wipe vigorously where your skin touched the poison oak. It can really prevent the rash from setting in. I follow that with soap and water, and coat my boots and pants with Tecnu spray.

First time at 48 getting poison oak

Got poison for first time and it put me in the bed for two whole days without being able to move very much because my whole body was in pain and body was going through hot and cold spells. Would not wish this stuff on my worst enemy. Please avoid at all cost because it real sucks!

Poison Oak relief

I don't Know why but the older I get the more allergic I seem to get. I've had it so bad before I've had to see a doctor for steroids. Well, once again it has started popping up on my arms. Rubbing baking soda paste (mix it with a little water) gave me relief for at least 10 seconds. I read that oatmeal may work. I'm not a big galloper so I didn't have any. Then I remembered that my dog's shampoo claimed to have oatmeal for my dogs itchy skin so I grabbed it and lathered my arms up. It works unbelievably well! It worked so well I decided to leave my new knowledge in this comment. And I never leave comments. I don't know if oatmeal alone will work better, I'll find out tomorrow, but I can tell you without a doubt, this dog shampoo is a god send tonight. Good luck.

Homeopathics for poison ivy

I do wash with Tecnu but I also take Sepia in whatever potency I have. For most people however, the homeopathic form of poison ivy - Rhus tox works. I had a systemic case and turned to a local homeopath for help when Rhus tox did not work and Sepia stopped it in its tracks and healing began overnight.

poison ivy

Bleach is not harmless to the skin, it is a terrible idea to put bleach on your skin, for any reason. It is destructive and can cause scarring. Ask me how I know.

Never Got it.....

I grew up around Poison Ivy on the east coast and could roll in it and not get it. My brothers bathed in calamine. Moved to the desert many years back. Recently , on a trip to Yosemite, we saw tons of Oak. I was not expecting to get it. Going on two weeks on my calf area . Ughhh. Picked up some Tecnu scrub which seems to help and calamine .

Poison ivy

I once got a terrible poison ivy rash on the underside of my upper arm. A horse I owned had (probably) scratched on a tree trunk vine. While I put my arm around her neck to place a halter I came in contact. It was a very uncomfortable area to get a rash !

Poison Ivy

The best cure is bleach. Rub straight bleach on the rash. It will not hurt your skin. It breaks down the oil and dries it up. The itching stops immediately and the rash or blisters will be gone in 2 days.

poison oak rash; ridding your land of it

Goats will eat poison oak without ill effects. Goats are in use by the University of CA in San Francisco to eat weeds, including poison oak, on their property. Poison oak rash is greatly relieved (although perhaps not like the potion described, infra) by placing ocean water on the rash. This is not indicated if you have an open sore (you have scratched the rash & it's open, oozing, infected) or if the rash is located in your privates.

poison oak nightmare during a pandemic

About 10 months ago got poison oak somehow walking around the woods I guess and I still have it it's January are you into the ER and they said nothing poison oak is nasty and it doesn't go away like ever and it reoccurs like every 3 weeks in the same spots that you've had it the whole time

Hedge

Cut my parents long and tall hedge years ago and was laid up for a week. Had to get a shot and was the most uncomfortable i've ever been. Be careful out there...
If you keep cutting areas with poison ivy or oak it will eventually die back.

Poison oak

Outside installing new license plates. Laid screw drivers on top of small poison oak plant unaware. Sweating from heat kept adjusting my glasses. I got an outbreak at the bridge of my nose. When I picked up tools realized it was po immediately showered with alot of soap. Didnt think about the nose area. Bingo..broke out at bridge of my nose. Broke out 4 days later

contact with it as a kid

Got it as a kid playing in the a forest with my friends. We got rid of it by rubbing the bottom of a fern bush leaf, and cold water on the infected area(I think thats what its called). The yellow spore/circles under them would come off on the skin and wash away into the river. The rash didnt go away but the irritation and pain did. It also stopped spreading. This happened quite often so it was cool that we could just keep playing.

Poison Ivy Salve

I make a salve with jewel weed, olive oil, vitamin E and beeswax. I don't have exact measurements; I cook the same was as did my mom.
I use a crock pot and put as much jewel weed that will fit in it. I cover it with olive oil and use the warm setting for at least 24 hours. If it boils it will burn the jewel weed and it won't be any good. I take the jewel weed out and strain it through cheese cloth. I put in more jewel weed and heat it for another 24 hours. This makes the oil stronger. I strain this as well and now I have jewel weed oil to make into a salve.
In a double boiler (I use a pot or pan) with boiling water and a glass bowl I put in about a cup of jewel weed oil and about a ounce of bees wax. (More bees wax if you want a harder salve.) Heat until bees wax is melted. If you want to add anything else this is when you do it. I sometimes add calendula oil as it soothes the skin and can help heal poison ivy as well. After it cools a bit this is when I add the vitamin E oil.
Pour into glass jars or medal tins and let solidify. Keep in the refrigerator as the only preservative it has is vitamin E and the cold salve feels really good on the skin.

Exposure to poison oak (extreme)

Two days after mowing around oak tree's in Texas ,I woke up and my eyes were swollen up so bad I could not even drive: couldn't breath right,it felt like a bad sunburn , red rash all over my neck and face. I was awful!!! Ambulance carried me to the hospital quickly. Now I have got two kinds of steroids to take and antihistamine . Its been two weeks and my skin is still not healed. Also it makes your skin peel like a bad sunburn, even in my scalp....GROSS!!!
Stay away from this stuff!!! I've tried aloe and calamine lotion ,but it didn't seem to work only the prescriptions seem to be helping. HELP!!!

Poison Oak Treatment

Sorry to hear you have a ba case.
You can check on WebMD and other web sites for over the counter treatments.
I'm dealing with a mild case of poison oak now for about 1 week. I seem to be under control
using over the counter Benedryl lotion and Tecnu scrub.

In the past, I needed to get a Steroid Shot to break the spread as it got into my bloodstream and would spread for over a month.
Do not take hot baths or showers, only cold to help prevent blistering. Try not to scratch the rash.

For the garden, Herbicides that are effective for killing poison oak include glyphosate (e.g., Roundup brand) and triclopyr (e.g., Ortho brand). You can apply herbicide to the stumps of cut plants or to the foliage of uncut plants, but both must be done while the plant is actively growing.
You physically removed the plants too. Whatever you do, Do NOT burn the leaves or branches. If you were to breath in the smoke, it would be time for the emergency room.

Poison oak

Hello, my name is Erin. I have never came in contact with this til just the other day in my front yard. It has been 4 days now and i've been having severe itching and redness as well as blisters. I need help to knowing how to get rid of it fast.

Poison Ivy and Oak and what of Ground Elder?

Ground Elder is a very tricky plant, scary in a way, it looks like Poison Ivy or Oak but is not poisonous. It is a ground vine originating from Europe.

Any suggestions anyone?

I have a nice "healthy patch" of poison ivy growing amongst my periwinkle plant bed and just wondered, any suggestions on how to kill the stuff? I just look at it and it makes me itch....well not really but it seems to be taking over the ground cover which once was nice and beautiful in the spring. Not any more. Any suggestions would be helpful...

Natural, no herbicide remedy to kill poison oak/ivy

How To Get Rid Of Poison Ivy Plants With Vinegar, Salt and Dish Soap

You can make a powerful homemade herbicide using a gallon of white vinegar, a cup of table salt (not Epsom salt) and a tablespoonful of dish soap.

Apply this mixture in the same way you would apply a commercial herbicide or bleach, except you wouldn‘t have to wear a hazmat suit! (You will want to wear long sleeves, pants, and solid shoes or boots to prevent contact with poisonous plants.)

Remember, if you plan to plant anything in the place of the poison plants, your application of table salt to the soil may prove problematic. Table salt will leach the soil of its nutrients. The soil will need amendments or you can simply establish a raised bed garden over it.

Many people have had success with this; however, it can take quite a few applications. If you plan to till the soil after the poison ivy has died, be very careful. The roots (even dead ones) contain active urushiol for up to five years.

Poison oak treatment

I got into poison oak two times as a child. It is true that you become more susceptible. The last time I had it I was about 33. I had just left for a short vacation with my husband and Friends, but I was suffering. It started on my upper arm as a tiny blister. I put something (can't remember), on the small rash then wrapped it with an Ace bandage. In the morning my arm was extremely swollen. I thought I would have to go to the emergency room, but instead called my doctor at home. He said to take Benadryl internally as well as externally on the rash. This relieved the pain and itch but did not heal it. I suffered through the day and night, but the next day went into the cool pool. Instantly, the pain and itch disappeared. I could feel the poison leaving my bloodstream. Other places where the rash had sprung out immediately went down. All that was left was flattened patches where the rash had been. I do believe that hot water, such as hot shower exacerbates it. It feels good, as if you're scratching, and I tend to think it has the same effect. So for me, Coldwater, and possibly the chemicals in the swimming pool healed it.

Poison ivy and poison oak rash

When I was a kid I always got poison ivy really bad. My mom tried everything and nothing worked. My grandpa told my mom to make me a hot bath and put a cup of Purex bleach in it. Then I had to bathe in the water until it got cold. I'm now in my late 40's and to this day I have not had but 1 small patch. So if you go swimming in a pool and you have either poison ivy or poison oak the chlorine in the pool will help.

Remedies for poison oak & poison ivy

A local herbalist, who has passed on, used to make a salve of Spotted Jewelweed (Impatiens capensis) which was the greatest healing product ever for poison oak or poison ivy. My oldest son is quite skeptical of herbals but this one he has thanked me over and over again for giving him.

Unfortunately, I know of no one who makes it anymore or even has a recipe. I was so hoping your article would have the recipe. I was surprised that the plant was not even mentioned.

jewelweed and poison ivy/oak

I've heard that the stalks and leaves of jewelweed can be crushed and the "juice" rubbed on the skin for relief of poison ivy. Try it!

Poison Oak

My son decided to make a 'crown of thorns' from a poison oak stem a few years back. He wore it on his head all afternoon in the hot summer. My sister wore it on her head too. The next morning she woke up with a rash on her face and neck. My son woke up with his head swelled so much he couldn't get his glasses on. He was having difficulty breathing. After a visit to the ER and daily visits to the doctor for over a week, the swelling went down. It was life threatening. Please do not underestimate the power of poison oak.

I have found that you can treat the blisters from poison ivy, oak, and sumac with Listerine. The plain brown colored one. It works as an astringent and helps take the itch out and helps dry up the blisters. We use it for all bites and rashes.

Poison - whatever

I thank God that I've never had any reaction to either poison ivy, oak or anything else! My brothers used to get it and my mom would make them soak in the bathtub with something called Blue Boro. I'm not sure if it's still made or whoever made it, but back then it seemed to help them - along with being covered with Calamine lotion. I've also heard that Fel's Naptha soap and bleach have worked for some people... just sayin...

I first got poison ivy in my

I first got poison ivy in my 40s and needed steroids to recover. I always thought I was "immune". You can become sensitive to it anytime, so be careful.

urushiol rash cure that works for me

I recently discovered this treatment and it has worked for me the last three times I used it. Soon after I saw a rash developing from contact with poison ivy, I mixed some calcium hypochlorite powder with water to form a paste and coated the afflicted area. The rash almost immediately receded. Calcium hypochlorite powder is available in a small packet at pool/spa supply stores. It is also the active ingredient in liquid bleach. So (I haven't tried this) making a paste with bleach and some inert ingredient should work exactly the same. It out-gasses small amounts of chlorine which I suspect reacts with the urushiol molecule to render it harmless.

Some people get nightmares MUCH worse than rash...

A "buddy" delivered some trunk-wood to me, neglecting to mention he didn't use it himself because it had been covered in heavy poison-something (I believe sumac). On a nice warm day, I chainsawed it into blocks wearing shorts (never mind the chainsaw-safety issue there). For hours, the saw shredded the tiny remaining fragments of the poison-X, and sprayed urushiol chips on my shins. Two days later, a BAD rash erupted all over my shins - angry red and white stripes like I had been whipped, not little blisters. The third day, I woke up soaked in blood, my skin "smeared off" on the bedding, and went to ER stat. I'll save you the details of the next few weeks, but I lost ALL the skin on my legs while changing massive antibiotic wet bandages to avoid SERIOUS infections. The pain was orders of magnitude worse than the emergency abdominal surgery I had a decade before -- unimaginable searing-blowtorch-while-being-fed-to-a-lawnmower pain. Happily, I avoided the feared infections, but the skin on my shins will never look normal again having been functionally flayed alive. So, don't write off poison-X as an inconvenience -- some people react VIOLENTLY if exposed more than trivially.

Warning!

When burning brush or yard debris - please be aware that the smoke from poison oak or poison ivy, if breathed in, can cause serious lung irritation.

- Also, pets who have been playing outside can get urushiol on their fur. It won't affect the pet - but it can be transferred to you when you pet or rub the animal or they rub against you.

- The urushiol from dead poison ivy / oak plants and vines can remain potent for years.

- There is a good video on YouTube that many may find helpful - look for "How to never have a serious poison ivy rash again"

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