Poison Ivy Oak and Sumac

poison ivy

Poison Ivy, Poison Oak and Poison Sumac- three nuisances parents and children alike, hate to encounter. These itching menaces can make someone downright miserable, so the following consists of identification and avoidance tips as well as treatment and other useful information to help you stay out of the way of itchy-red-madness-central.

Where can you find ‘em and what do they look like?

Poison Ivy- In the east, midwest and south US it grows in vine form, while in the far northern and western US, Canada and Great Lakes area it grows as a shrub. In both forms, each leaf has three shiny leaflets
Poison Oak
In the West US, this plant sometimes grows as a vine but usually is a shrub. In the East, it grows exclusively as a shrub. Look for hair growing on its fruit, trunk and leaves. The leaves have three leaflets.
Poison Sumac
Grows in standing water in peat bogs in the Northeast and Midwest and in swampy areas in parts of the Southeast. Each leaf has in between seven and 13 leaflets.

poison oak

Poison ivy, oak, or sumac are found in every state except Alaska and Hawaii. Nevada has some poison ivy along its eastern border with Utah, and Idaho has poison ivy along it’s western border with Oregon. These species (and sub-species) are so successful because they adapt easily and are hardy plants- their requirements are few- eight to ten inches of rainfall a year and an altitude of under 4,000 ft.

poison sumac


What makes these plants so volatile is the fact that they all emit and produce a oil known as urushiol. urushiol is an interesting oil in that it affects everyone differently, further down the page you can find information on urushiol sensitivity. As an oil, and not a water based fluid urushiol has some special qualities…

It does not evaporate, so it can last for years- even on dead plants.

It tends to coat everything it comes into contact with animate (living) or inanimate (non-living).

It vaporizes when burned- the vapor then covers everything it touches.


One of the first signs is redness and itching where the plants (or objects in contact with the plants) touched your skin.

This redness then swells and develops into a rash, that usually is in streaks or patches, again consistent with where there was contact with the oil.

The red bumps of the rash may become large weeping (oozing) blisters. The fluid that comes from them should be clear, and when it dried will harden to a yellowish crust. Never break these blisters!!

The rash is usually worst 4-7 days after being exposed to the toxin.

The rashes may last for about 1-3 weeks. If you leave it completely untreated, it will typically last 3-5 weeks.

Most often symptoms appear within two days of being exposed, but occasional it takes up to two weeks.

Reactions to the urushiol oil vary from person to person, from mild to severe. In some severe cases hospitalization is needed, so if you think your reaction may be severe seek help.

However, if you can catch it before symptoms develop…
Urushiol “locks on” to the skin within about 20 minutes of being exposed to the oil. So catching it fast may stop a reaction before it even begins. Remember, that while there is no cure for these reactions, there are many ways to minimize the suffering.

First off, wash any skin that may have come into contact thoroughly with warm water and a mild soap. washing it off quickly may avoid a reaction altogether. Be sure to wash hard to reach places like under fingernails, to avoid spreading the oil via scratching. Remember, that even if you can’t wash it off right away, washing within the first 6 hours can at least help minimize the extent of the reaction.

Next wash everything else that may have touched the plants with hot water and soap (Oak-N-Ivy®). This includes clothing, shoes, gloves, tools, work gear, and Pets! Animals can carry the oil on their fur, but are often not affected by the toxin themselves. When it comes to gear and tools, a cleaner like Tecnu® Cleanser can remove the oil to prevent others from becoming affected. remember that the oil can linger for a very long time, so it is important to remove it from anything it might have touched.

If you do have a reaction, try and keep cool. Body heat and sweating can aggravate itching. Applying a cool pack wrapped in a towel can help calm itching urges.

Other ways to alleviate itching can come from calamine lotion, zinc acetate or hydrocortisone cream can be applied, or an antihistamine may be taken. Another soother is a bath of tepid water with one cup of Aveeno oatmeal. As difficult as it may seem, *not* scratching, will also help, it also helps preventing further damage to skin.

Blisters. They’re ugly, and they aren’t pleasant but Do Not break them! Breaking the blisters can lead to blood poisoning or further infection. Try your hardest not to scratch them. Allow the blisters to breathe. If you wrap them change the dressings frequently, and make sure the area stays clean- this helps prevent infection. If a blister does break, cover it loosely with a sterile bandage, change the bandage often, and make sure the area stays clean. If a blister looks infected, or gives you other reason to worry, seek medical help.

If new rashes start to appear several days after the first set shows up, then you are being re-exposed to the oil. Double check everything that might have come into contact with the plants, either at that time, or since that time- pets are usually high on the list if there is ivy/oak/sumac growing near or in your yard.

When to seek medical attention

The victim is suffering a severe allergic reaction, such as swelling and/or difficulty breathing, or has had a severe reaction to a past exposure.

The victim has been exposed to the smoke of a burning plant.

The rash covers more than one quarter of the body.

The victim is suffering severe itching in the face or around the genitals.

The blisters look or become infected. Do Not

Do not touch with your bare hands, the skin/clothing etc of someone who has come into contact with urushiol, until the area has been well cleaned.

Do not use bleach to try and ‘burn’ away the urushiol oil. you will only damage your skin, by exposing it to other nasty chemicals.

NEVER burn any of the Poison I, O, S. plants! urushiol remains on dead plants for years and it is found in the leaves, roots and stems of all these plants. Burning the plants exposes others to severe and serious internal and external reactions via inhalation and external contact with the smoke. The smoke can travel for miles and will leave a fine coating on whatever it touches, which can further expose people to the toxin.

In many states it is illegal to burn poisonous plants. Common misconceptions

Spreading the rash- Spreading poison ivy has kept many kids out of school- because parents were afraid of spreading the rash. Luckily, the rash is not actually ’spreadable’ - only the urushiol oil is - so if you make sure that you’ve cleaned all the oil from the skin your child should no longer be able to contaminate anyone else. However, If you are unaware your child has come into contact with the pants, or something touched by the plants, because symptoms have not shown up yet, your child is still able to spread the oil to anyone who touches them for several days following the contact. Another misconception, touching or scratching blisters, and the fluid in them, will spread the rash. This is also untrue, the only way to spread the rash is my spreading the oil via scratching if you haven’t washed it all off, or being unknowingly re-exposed and having others touch you, or things you touch and get oil on.
They’re dead, right?- Urushiol is like an enemy that almost never sleeps. It remains on dead plants for up to several years! Because of this, never touch the plants, even if they look dead. And again, Never burn them.

Avoid That Itch!
Luckily, there are lots of ways to avoid becoming a victim of the itch. First off, when outdoors keep yourself covered! Long pants, long sleeves, or ivy/oak/sumac barrier creams can be helpful. Urushiol can stick to clothing, so keep in mind that even if you’re covered clothing wise, your hands could touch the contacted area and then you could potentially spread the oil anywhere that your hands touch. Showering and washing the clothing you wore out, upon your return is a good way to prevent a rash from appearing if you were in an area known to contain such plants. Another simple way to prevent a problem is to learn how to recognize the plants and avoid them when you’re outside.

Are you sensitive?
Nobody is born allergic to urushiol oil, and you wont know if you’re allergic until your first encounter. If you happen to be one of the 15% who isn’t affected by the oil, consider yourself lucky- at least for now. Urushiol is tricky, you may be immune to it one day, and allergic the very next! And even trickier, usually a person does *not* have a reaction the first time, yet the second encounter may yield a severe reaction. If you’re lucky enough to reach adulthood without suffering a reaction (and have come into previous contact with the plant) then your chances of becoming sensitive are decreased to about 50%. Sensitivity levels vary from person to person, and there does not appear to be any genetic link.
Sensitivity decreases with age and repeated exposure. Most people who suffered often as children will find that if they were prone to repeatedly being exposed when they were young, that by the time they’ve become young adults their sensitivity will have decreased by about half- and their reactions will be less severe. Sometimes people who were once allergic, become desensitized and immune later in life.
Some people are incredibly sensitive to poison plants. Their reaction can include severe swelling and blisters around the face, genitals, arms and legs. Sometimes people will have a reaction that acts like other bad allergic reactions- complete with breathing difficulties, throat swelling, etc. People who have reactions like this need to seek medical treatment.

As irritating as these plants are, they’re important to the ecosystems they’re a part of. Surprisingly, while most people are irritated by urushiol, very few animals seem irritated by it. All different types of animals are able to make their homes in the briars and tangles of the vines, and birds and small animals alike eat the small berries that grow on ivy plants. However, since you aren’t an animal or bird, we do not advise either eating the berries, or trying to make your home in a patch of ivy vines. Instead, use the tips given above to avoid the plants, and if you do happen to encounter them, take the correct measures to avoid or deal with any reaction that occurs. Happy Hiking!

*** Before administering any first aid to anyone outside your family, be aware of your rights and responsibilities: The Good Samaritan Law. ***