Poison Ivy Problems

Leaves of three, let it be. Every year, dermatologists see patients that have rashes, swelling, and blisters, sometimes severe ones caused by poison ivy, poison oak, or poison sumac. Armed with some knowledge though, you can take precautions to minimize an unpleasant experience.

What is Poison Ivy and Why do I get a Rash?

Poison ivy is actually not a poison. The rashes that result from coming into contact with poison ivy is actually due to your immune system attacking your skin--it’s an allergic reaction to a plant oil called urushiol. Poison ivy, poison oak, and poison sumac are the common plants in North America that contain this oil. Elsewhere in the world, mango trees and lacquer trees also contain urushiol. Not everyone is allergic to this substance, but it’s estimated that about 85% of people have some type of negative reaction to urushiol, and 10 to 15% are extremely allergic1 so it’s definitely something you want to avoid. Once you understand the mechanism, you can understand a lot of the mysteries surrounding poison ivy and how to minimize the chance of exposure.

  • You can get a rash not just from direct contact with the plant, but from coming into contact with your pet, who may have come in contact with the oil. (Your pet is usually fine being protected by fur, and the allergy seems to be human-specific)
  • Other forms of indirect contact are also possible, like touching objects that have the oil on them.
  • Burning these plants can release the oil particles into the air, causing a reaction not just to skin, but to the eyes, nose, and lungs.
  • Poison ivy rashes are not contagious.

What do I look for and what do I do?

Generally, there is a slight delay of about 24 to 48 hours after contact, at which point, symptoms begin to show (unless you are a lucky minority who doesn’t react to urushiol):

  • Rash (often in streaks)
  • Swelling
  • Inflammation
  • Burning sensation

*If these rashes are severe, cover a wide area, or sensitive areas like the eyes, lips, or genitals, or become infected, see a doctor right away. If you’re unsure of whether you should see a doctor or not, it’s a good idea to be on the safe side and visit a doctor.

If the symptoms are mild, they will generally subside after 1 to 2 weeks. If the symptoms are mild, you may want to manage the rashes yourself.

Step 1: Decontaminate

Clothes like socks, shoes, tools, and pets that are likely to have come into contact with urushiol (the poison ivy oil) need to be thoroughly washed. The last thing you want is to leave around items that have come into contact with urushiol. Urushiol can remain active for up to 5 years away from the plant, meaning that you would get “poisoned” the next time you come into contact with the contaminated object.

Step 2: Self Care

Gently wash away the exposed skin using mild soap. A cool compress (an ice pack will do) can provide some temporary relief, especially when the skin is blistering. Baking soda and water mixed, can create a DIY calming lotion for itchy or painful areas. If you show no signs of improvement after a week, it’s a good idea to check in with your doctor.

Step 3: Prevention

A lot of the prevention is already done in the decontamination step. Coming into contact a second time by touching contaminated surfaces, usually a tool, is extremely common, possibly the most common way to expose yourself.

  • Wear long sleeves and leave the skin covered when going out for a walk in the woods. This is mandatory for people who work in outdoor environments.
  • Leaves of three, let it be. This preventative adage isn’t always accurate, as it’s only poison ivy that has three leaves. Poison oak and sumac don’t follow this rule, but poison ivy is far more ubiquitous so it’s a good guideline nonetheless.
  • There are some lotions that can be pre-applied to prevent or minimize the chance of coming into contact with the oil.