In the 100th year of operation of Camp Nyoda, I unpacked my eight year old daughter’s camp trunk and made her bed, hung her laundry bag and robe on the runway, and dutifully organized her shelf. I am embarrassed to say I was one of the last parents to depart on opening day, not because I was lingering intentionally, but rather because I knew almost too well what I was doing and spent way too much time trying to do it just right.
This meant that my then six year old son was bored and exploring, as bored six year old boys do. We found him sitting on a rock between the Junior bung and the shower house in a field of green…green grass, green weeds, and a bed of green poison ivy. I didn’t panic for his sake as fortunately he hadn’t yet experienced the blistering poison ivy my husband and I have gotten annually since moving to the suburbs. I wasn’t always allergic, however. I often wonder how I survived so many summers at Nyoda and never had a rash of that sort. Seemingly, I developed this hypersensitivity at some point in my adulthood and ever since, I endeavor during spring and summer months to seer as clear as possible.
In my experience, many people do not realize a number of truths about poison ivy. First and foremost, it is not “poison” but rather a highly allergenic plant species (Toxicodendron radicans) that contains a contact allergen named urushiol, which is found in poison sumac (Toxicodenrum vernix, found in the Southern United States). These are among the most common causes of allergic dermatitis in North America.
Allergic contact dermatitis, such as poison ivy dermatitis is a type IV, delayed-type hypersensitivity reaction. It occurs when the skin come into contact with specific allergens that then trigger an immune-mediated response in a sensitized person. The allergen is initially taken up by specialized cells called dendritic cells residing in the skin that subsequently migrate to local lymph nodes and present these antigens to T cells, essential components of the immune system. These newly activated or sensitized T cells are able to proliferate and migrate back to the skin where they may be activated more readily upon future exposure to the allergen (in the cause of poison ivy, urushiol). This activation results in a release of molecules called cytokines which promote local inflammation, in turn causing redness, swelling and sometimes blistering of the skin. While initial sensitization may occur as late as ten to fourteen days from the time of exposure, repeat exposures may result in a skin reaction within one to three days. An individual may develop a hypersensitivity to urushiol after many years of chronic or repeated exposure to the plant without incident.
Poison ivy has a pattern of three deciduous, slightly shiny leaves, hence the phrase “leaves of three, let it be.” Leaves range from green to reddish-brown depending on the season and have few or no pointed teeth along the edges. It is found throughout North America and in parts of Asia. Urushiol is an oil made by Toxicodendron species that may be highly allergenic in sensitized individuals. Following contact with the skin, it may cause itchy or painful rash at the site of skin exposure. While many believe this rash is contagious or spreads on theskin, progressive skin involvement is a result of delayed reaction to direct of indirect skin exposure to urushiol. Once this rash has developed on the exposed individual, it does not spread from person to person. However, secondary contact with recently exposed skin may result in a rash (if oil from the plant is still present). For example, Fido the dog can run happily through a field of poison ivy and avoid a rash, while transmitting a fair amount of urushiol from his fur to your skin when he comes home for a cuddle.
While some people find the rash to be nothing more than a nuisance, others find it intensely itchy and sometimes painful. The rash is typically characterized by pink bumps and clear fluid-filled small blisters, often in a streaky or linear pattern. It is important to note that these blisters are the result of intense inflammation and swelling within the skin rather than actual plant fluid contents. The contents of these blisters are not contagious. Involvement of the face may result in significant eyelid or lip swelling due to the thinner, more fragile skin in these locations.
Most cases of poison ivy can be treated successfully with topical corticosteroid cream and/oral antihistamines to reduce itching symptoms. Severe or extensive cases can be treated with a corticosteroid administered orally or intramuscularly. For those with mild symptoms, topical calamine lotion may suffice.
When we found our son sitting on a forest of poison ivy last summer, we calmly had him get himself back in the car without contacting his skin, and shower quickly at home. As it turns out, this exposure at camp did in fact result in his first experience with the rash of poison ivy, which we treated with topical corticosteroid cream and oral antihistamines.
Our take home lesson? Unpack our daughter faster on opening day this year, for everyone’s sake!