What You May Not Know About Poison Ivy

Poison Ivy leaves of three.

Considering that it can be found in almost every part of the United States, it’s hardly surprising that almost everyone is at least passingly familiar with poison ivy. However, the fact that it is extremely common has also led to the spread of several misconceptions about this plant. 

This article will serve to introduce you to some of the least known and understood facts behind poison ivy, as well as debunking a few of the more common urban myths that surround it. 


The Cause of a Reaction

Many people are not aware that the allergic reaction from poison ivy is not actually caused by the body of the plant, but rather by urushiol, the waxy oil produced in poison ivy sap which will naturally spread over the entire plant. The reaction happens when urushiol comes into contact with bare skin and isn’t washed off immediately. 

Long-Lasting Oils

Since the reaction comes from the oil and not the actual leaves or stem of poison ivy, this means that you can still get a rash if your skin comes into contact with clothing or other items that have urushiol oil on them.  

Indeed, it may surprise you to learn that urushiol that has been wiped on a surface like clothing or an outdoor tool, can survive on that surface for months or even years without losing its toxic potency -  it can even be carried on a pet’s fur! This is why it is so necessary to carefully wash anything that has come in contact with poison ivy.

Urushiol Is Found in Several Plants

It’s probably not surprising to learn that other plants related to poison ivy also will naturally produce urushiol - poison sumac and poison oak are both close relatives that produce urushiol, and will cause the same kind of rash if exposed to human skin. 

What is surprising is that pistachios, cashews, and mangos also produce this chemical compound, although not enough to provoke a reaction in humans. 

Poison Ivy Rash

Not as Contagious as Some Claim

It’s a fairly common myth that the rash caused by poison ivy is highly contagious. Some claim that coming in contact with a poison ivy rash is all it takes for the rash to spread from person to person, or for it to expand across different parts of the body.

Fortunately this is not true. You can only get a poison ivy rash by directly coming in contact with urushiol, although a rash can spread if someone gets fresh urushiol on their fingers and touches their own, or someone else’s body. 

Being “Immune” to Poison Ivy

You may have met someone who claims to be immune to poison ivy. While this is technically possible (10-15% of people will genuinely not react to it), it’s more likely that they simply haven’t been sensitized to it. 

The rash is caused by your immune system reacting to a foreign threat, but the first or even second time that you come in contact with poison ivy, your body won’t be able to recognize urushiol as dangerous. This is why most people will only develop a rash on their second or third encounter with the plant, once their immune system “learns” to recognize poison ivy as dangerous. 

Dead Plants Can Still Cause a Reaction

If you’re planning to clear some poison ivy off your property, or see some growing in the wild, don’t assume that it’s safe to touch just because the plant is dead! Just as urushiol can last for years when rubbed off on clothing, that same oil will survive comfortably for years, even through high temperatures, very acidic environments, and the death of the poison ivy itself! 

Other Facts

Climate Change is Making Poison Ivy Worse

In recent years, climate change has had two effects on poison ivy. First, it has contributed to the spread of the plant around the country - fires, floods, logging, and other events either causing or resulting from climate change have the result of opening up the forest canopy. This allows more sun to reach the forest floor, where the ivy grows, thus creating more ideal growing conditions. 

Secondly, rising temperatures and carbon dioxide levels are contributing to an increase in both the spread of the plant, and the toxicity of urushiol. 

Tecnu Knows Poison Ivy Treatment 

At Tecnu, our goal is simple: to create innovative products that help our consumers solve a problem. 

Our team continually strives to find new and better ways to not only meet, but to exceed the needs and expectations of our customers. We vow to stay on the path of advancement without losing sight of who we are at our core: a driven group of individuals with a desire to help others, whether they be outdoor adventurers, gardeners, athletes, moms, dads, or all of the above
Tecnu offers the industry’s best treatments for poison ivy, poison oak, and poison sumac. Our Original Outdoor Skin Cleanser and Extreme Poison Ivy Scrub helps wash away the culprit (urushiol).