You probably know the rhyme, but if you’re itching to spend time in the great outdoors this summer, being exposed to poison ivy probably isn’t what you had in mind.

Layla Faragallah came into contact with poison ivy several weeks ago, and except for a few scars and dried blisters – most of the physical symptoms are gone. 

But the memories of the discomfort she experienced haven’t yet disappeared.

“The itching was so bad that I actually missed two days of school, I couldn’t really walk, or get out of bed,” Faragallah said. 

Poison ivy can be difficult to identify – so watch out. 

Poison ivy has a distinctive appearance, featuring a cluster of three pointed, elliptical-shaped leaves. The middle leaflet is longer than the outer two, and it grows as a vine or shrub (depending on geographical location) and may have bunches of white or green berries. The leaves can have a smooth or jagged edge, and appear green, but may fade to red, orange or yellow in the spring or autumn months. Another feature that makes poison ivy stand out is its glossy surface. 

“It can be, probably trickier to identify poison ivy, poison oak, poison sumac, than you might think. All these plants can appear differently depending on the area of the country they’re in, the time of year, the weather,” said Catherine Roberts, Consumer Reports health editor. 

Poison ivy has a diverse range across Canada, being found in every province except for Newfoundland. In British Columbia, it is known as western poison ivy, and is found in the south-central region, predominantly in the Okanagan Valley. 

What makes poison ivy so poisonous?

Just brushing up against a poison ivy plant can deposit its oily coating, called urushiol, onto your skin. Eighty to ninety per cent of the population is allergic to urushiol. 

Exposure to the oil then triggers an allergic reaction which develops into a red, itchy rash. It’s important to note that you can only develop an allergic reaction by coming in direct contact with the oil, and not the blister fluid.

The rash usually takes more than a week to appear the first time you react to the oil and it will develop in a day or two on later contacts. You will only get a rash where the oil touched your skin, and it usually lasts about 10 days to three weeks, but it may last up to six weeks in severe cases.

Common rash symptoms include itching, red streaks or general redness where the plant brushed against the skin, small bumps or larger raised areas (hives), or having blisters that may leak fluid. As difficult as it might be, refrain from scratching the rash, as it could cause a skin infection.

“Only folks who are allergic to one of these plants will react, but most people are allergic. And it can happen immediately, right after you’re exposed or it can take up to four days for the rash, the swelling, the blisters to appear,” said Roberts. 

Some scientists believe we might see more severe cases because of climate change and longer growing seasons.

Because the plant can be anywhere from the woods, to parks, or even your own backyard, there are several things you can do to reduce your exposure. 

For example, wearing long-sleeved shirts and long pants can offer protection, and if you even think you’ve been exposed, clean your skin with soap and water immediately. Other tips are to use an ivy blocking cream if you’re spending a lot of time outdoors, and thoroughly clean any tools that might have residual oil on them.

“Scrub your skin, really thoroughly, get under your nails –– but you also want to wash your clothes, your gardening tools even your dog. That residual oil can transmit the rash and the oil can linger for years,” said Roberts.

Other remedies include applying calamine lotion, oatmeal baths and cool compresses. These can offer some relief, but if they aren’t helping, experts recommend taking a trip to a dermatologist. A dose of steroids can be effective in stopping the itch faster.

Keep in mind that burning the plant is also ill-advised, as the oil can attach itself to smoke particles and irritate your skin, eyes and nose. If inhaled, it can cause damage to the lungs.

Just ask Faragallah, while topical creams may help - only time will stop the itch.

Also be on the lookout for poison ivy’s two equally unpleasant cousins, poison oak and poison sumac. Remember, “leaves of three, let it be!”