Poison ivy is a toxic plant that is commonly, but not exclusively, found through most continental areas of the United States.

It tends to grow in totally wild areas but is also found in places which have seen human disturbance, such as road sides, sidewalks and trails or anywhere where there is a cleared or well developed plot of land.

One of its characteristics is its ability to grow and flourish where other plants cannot. This makes it relatively easy to spot and identify.

Many people have had reactions to Poison Ivy, and for the most part they will be mild and easy to treat at home using medicines which can be bought over the counter from a reputable drugstore.

There are sometimes more severe cases which will need better medical treatment. We’ll outline both ways here and how to identify the symptoms of Poison Ivy, too.

What is Poison Ivy?

Poison Ivy is also known as Toxicodendron Radicans, this alongside Poison Oak and Poison Sumac are plants which, if put directly into contact with skin can cause an itchy and uncomfortable rash.

There is a substance within all these plants called urushiol which is responsible for causing the flare ups.

It’s important to know that the rash, although unpleasant and uncomfortable, is not in any way contagious, and will disappear with the right treatment, after one to three weeks. Most cases of either Poison Ivy, Poison Oak or Poison Sumac can be effectively treated at home. Though sometimes, it is necessary to seek medical attention from a qualified health professional if your symptoms worsen or become more painful.

How Can We Identify Poison Ivy, Poison Oak and Poison Sumac?

You’ll find that poison ivy typically grows as a shrub, or as a vine. It’s typically found through most places in North America – though not in Alaska, or Hawaii or the desert regions. It crops up in open fields, in areas that are wooded or on riverbanks or the roadside. It will also grow in urban areas, and in parks and also in homeowner’s backyards or gardens.

You can identify poison ivy plants by their leaves which are usually clustered in groups of three, this can sometimes vary but for the most part is standard. The leaves color and shape will vary depending on it’s species, where it is growing, and the time of year. The flowers on poison ivy plants tend to be yellow or green, with white or greenish yellow berries. Again, this is dependent on the season.

There are also two different subtypes of poison ivy; Eastern and Western:

Eastern poison ivy is distinguished by the fact is grows a rope-like looking vine.
Western poison ivy will grow as a low shrub.

Poison Oak

Closely related and of the same family, it can also be useful to know how to identify both Poison oak (Toxicodendron diversilobum) and Poison Sumac (Toxicodendron vernix).

Firstly, poison oak will also grow as a shrub or as a vine. It tends to be more associated with the Western side of the USA and also to be found in British Columbia. It’s leaf arrangement is similar to poison ivy, with clusters of three leaves. However, they differ in the sense that they can sometimes (but not always) resemble the leaves of the proper oak tree.

Poison Sumac

Poison sumac grows in the form of either a small tree or shrub, rather than a vine. This will be found in the Eastern and South Eastern side of the USA, and it is found in the eastern/south-eastern United States. It prefers a wetter, and more humid climate and tends to be found a lot along the banks of the Mississippi River. The stems of Poison Sumac contain between seven and thirteen leaves. This particular plant has the ability to cause a much more severe rash/reaction than either poison ivy or poison oak.

Signs and Symptoms of Poison Ivy Rash

Susceptible people will develop a poison ivy rash anywhere between twelve and seventy two hours after contact with the plant. Signs and symptoms of poison ivy rash may be:

  • Skin which becomes very red
  • Swollen skin
  • Itching skin
  • Outbreaks of small to large blisters

A rash, which could be bumpy, patchy, linear or streaky in appearance. The rash may be more severe if a larger area of skin has been exposed to the urushiol oil that is found in the plant. Depending on the severity of the rash, new patches may still appear for up to three weeks after the initial contact. The rash is not contagious to other people but it is perfectly possible to spread it to other parts of the body if your hands become contaminated with urushiol and then you go on to touch other areas of yourself. The rash will slowly improve over the course of three weeks and any accompanying symptoms will be mild, to moderate to severe. In very rare cases, some people can develop an anaphylactic reaction. In these cases, treatment at an ER is the only option. If anyone in the near vicinity to you burns the plants, the oil urushiol can be released which can again cause a reaction. Stay inside with doors and windows closed until the fumes/smoke die down. If you notice any reaction, report to a Doctor immediately, or attend ER.

Frequently Asked Questions About Poison Ivy

What are the causes of a poison ivy, oak, or sumac rash?

If you’ve been exposed to these plants, you might develop a rash. This rash is caused by the oily resin found in them, called urushiol.

Urushiol is found in the leaves, stems, flowers, and roots of these plants. You might think that once the plant dies, it poses no risk and therefore you’re safe if you’ve come into contact with it. This is false, the urushiol is still active even after the plant has died. You need very little to experience a reaction, particles of urushiol as small as a grain of salt can cause rash in around 80-90% of patients.

The rash is almost identical to contact dermatitis, and is caused by direct contact with urushiol by touching the plants or indirect contact with the plant oil (unlike chia oil that helps nourish your skin!) that may have contaminated a pet’s fur, tools, clothing, or other surfaces.

You can also have contact with urushiol via the air if the plants are burned and particles land on the skin or are inhaled. In the United States, poison ivy/oak or sumac are the most common cause of contact dermatitis.

Individuals become sensitive to urushiol when they first come into contact with it. Sometimes they might not develop a rash the first time but if they’re exposed to it often enough sensitivity develops and a rash may follow. Most people – in fact around 85% – will develop sensitivity, however, the remaining 15% will never develop a rash or sensitivity.

Are there risk factors for developing poison ivy rash?

Simply coming into contact with the plant is enough. However, people who spend more time outdoors and who are in the areas of the USA where these plants are known to grow are at higher risk.

There are naturally certain jobs that put you at greater risk of being affected – these include This may include gardeners, groundskeepers, farmers, forestry workers, and construction workers. If you’re generally an outdoors person and love hiking, walking or running you’ll be at a higher risk of developing a rash if you go to areas where these plants are present.

Treatment for Poison Ivy Rash

When your skin erupts after contact with poison ivy there are a few treatments you can opt for. There are a couple of old wives’ tales that should definitely be avoided. One of these is using human urine to douse the site of the rash, the other is using gasoline on the rash. Neither of these should be attempted. In most cases needing treatment it is better to visit a Doctor and get a prescription for topical steroid cream, or tablets. These should be used according to your healthcare practitioners instructions for a period of one to three weeks.

However, there are some first steps you need to take to help yourself along. Initially, rinse the affected area of skin with fresh, warm water within twenty minutes of exposure to the plant. This will remove some of the resin. Rinsing won’t have any effect if you leave it longer than thirty minutes as by that time the resin will have absorbed into the skin. You may also be told that swabbing with rubbing alcohol or using degreasing soap to wash the skin will help.

Another important point to remember is to scrub under the fingernails to remove the resin from there too. Immediately wash all clothing and clean any surfaces you may have touched. Normal detergents will be enough to tackle this. If your child’s skin has come in contact with poison ivy be sure to only use products that you know they don’t react to. It would be awful to aggravate their poison ivy rash further!

Signs of Poison Ivy

How to Stop Poison Ivy Rashes

How is Poison Ivy Diagnosed?

If you think you have been affected by the rash, you’ll need to see a Doctor who will be able to examine you to make the right diagnosis. The appearance of a rash is all that is needed to make the diagnosis. There is no need for blood tests.

In many cases the rash will improve on its own after one to three weeks. You can try the following ideas to relieve any symptoms:

  • Cold compresses or ice packs on the skin
  • Calamine lotion
  • Oatmeal lotions or baths
  • Tecnu, Zanfel, or aluminum acetate (otherwise known as Domeboro solution).
  • Taking an antihistamine to relieve itching
  • Sometimes steroid creams are prescribed (such as prednisone).
  • OTC medication for pain relief such as paracetamol or sometimes ibuprofen
  • If the rash is infected, antibiotics might be prescribed

In extremely rare cases an anaphylactic reaction could occur, this is characterized by difficulty breathing, difficulty swallowing, facial swelling, or if one has had a previous severe reaction to these plants. In these cases, go straight to the ER for further help and advice.

Can I treat poison ivy at home?

Yes, this is perfectly possible. Most or all of the symptoms can be treated safely and effectively at home once a diagnosis is made. You would only need to seek further help if the rash did not go away after a month, or you developed other more serious symptoms, as outlined above that required a trip to ER. If you have managed to get the rash on your face make sure not apply any makeup as it may have a negative effect.

Will I recover from poison ivy?

Yes, you will recover. Once the rash has gone you should suffer no other complications. There are steps you can take to prevent further exposure, or from contracting another poison ivy rash. These are as follows:

  • Learn how to spot the plants so that you know to keep away from them if you see one in the future.
  • If you know you may possibly be going into an environment where poison ivy is present, wear protective clothing, including gloves, long sleeved clothing and boots.
  • Use barrier creams on exposed skin, if you know you’ll be exposed to it. Look for something that contains bentoquatam. Apply this liberally to all exposed skin before going outside.
  • Never burn poison ivy/oak/sumac.
  • If you have to remove such plants from your home, be very careful, wear protective clothing, gloves and a face mask. Afterwards, wash all clothing and shower thoroughly and carefully
  • If a pet has become exposed, bathe or shower them – you must wear protective clothing and make sure you shower and wash your clothes afterwards.
  • Now that you know how to identify and treat poison ivy, let’s take a look at some of the common myths and misconceptions that surround it.

Common Myths and Misconceptions about Poison Ivy

Poison ivy is contagious

The rash cannot pass from person to person. Urushiol can be spread by contact, so it’s important that if you’ve been exposed to it you keep your skin clean, wash any clothes and surfaces you have touched and advise anyone else you’ve been in contact with to do the same.

If you scratch poison ivy blisters, you’ll spread the rash

No. As mentioned above the rash comes from the urushiol found in poison ivy, oak and sumac. If the oil is on your hands and then you touch other areas of your body the rash will spread to those areas. Fluid found inside the blisters won’t case additional spreading of the rash.
Do not break poison ivy blisters as there is always the chance your skin could become infected. Keep hands and fingernails clean. If there is a lot of fluid building up in your blisters, seek medical advice.

“If it has three leaves, let it be”

This rule works for poison ivy – if you spot a plant with three clustered leaves, don’t touch it. However, poison oak and sumac are different. Poison ivy has 3 leaves per cluster. Meanwhile, poison oak usually has between 3 to 5 leaves, and poison sumac has between 7 to 13 leaves on a branch. Knowing these facts means you’re more likely to be able to spot and avoid all three types of plant!

Only poison ivy leaves are poisonous

Again, no. There are more cases of rashes in summer when leaves on poison ivy plants are more abundant. It’s perfectly possible to still contract a poison ivy rash in autumn and winter when there are less leaves present. This is because every part of the plant contains urushiol oil including the leaves, roots, flowers, stems, vines and berries, so all must be avoided at all times. Even when the plant appears to be dead, urushiol will still be present, which brings us to the next point…

If poison ivy is dead, it isn’t toxic

If the plant is dead, it still needs to be avoided and should never ever be burned. Urushiol oil can stay active on surfaces, including dead plants, for up to five years or longer. If you’ve come into contact with a dead plant, you must still follow the same precautions as if you had touched a live poison ivy

If I haven’t had a rash from poison ivy, I must be immune

There are some lucky people who don’t get an allergic reaction to the poison ivy when they come into contact with it. This doesn’t mean they’re immune. They could likely touch it a few months later and get a rash then. Sometimes it takes multiple exposures for a problem to develop. Susceptibility can occur over time and from season to season.

If you eat poison ivy, you’ll get immunity

Please don’t do this. Never, ever chew or eat, or swallow poison ivy, sumac or oak leaves. It is dangerous and very untrue. You could end up with a rash in your mouth or in your lungs, which is very dangerous indeed. If you have had poison ivy leaves in your mouth, go to ER immediately and seek medical assistance.

The best course of action for cases of poison ivy is to keep your skin clean, make sure any clothes that have come into contact with the plant are washed with detergent and to take steps to make sure any rashes that develop are kept cool and clean. If you feel unwell or develop any other unusual symptoms after exposure to poison ivy seek advice at your ER.

References and Further Reading