Description
Poison ivy can take several forms: shrubby, low-growing and ground-covering or climbing. You can find it especially near the woods, in empty spaces and along roads or rivers.
The leaves of poison ivy are shiny and each has three pointed leaflets. The central leaflet’s stalk is much longer than the side leaflets. The edges of the leaflets are smooth or toothed, rarely lobed. Leaf size varies between 8 and 55 mm long and the color is reddish when they emerge in the spring but gradually become green in the summer and then take on various shades of yellow, orange and red in autumn. Poison ivy produces flowers cream to yellow-green in June and July. In September, globular, waxy fruit the size of a dry pea appear and can remain bare on the plant all through winter.
If you go visit the Botanical Garden, you will have the opportunity to see poison ivy in the Toxic Plant Garden.
Protection
Learning to recognize poison ivy and to be able to avoid is actually the best way to protect yourself. If you are planning a hike in the woods, try to wear long sleeves, pants, boots and gloves to minimize the chances of contact.
Contamination and Causes
The rash that occurs after contact with poison ivy is caused by a nearly invisible oil, clear or slightly yellow, which is called urushiol and which escapes from any damaged leaves, stem or roots on the ground. It’s important to note that this oil can also contaminate the pads or the fur of dogs and cats for a period of up to 3 days and that even shoes, clothing and garden tools can also be infected for weeks or even months.
The reaction to urushiol being an allergic reaction, most people are not affected during the initial contact but will develop a heightened sensitivity that makes it so subsequent exposure may lead to dermatitis. You can usually notice the symptoms appearing within 24 to 48 hours after contact with the plant, an object or an infected animal. The severity of the reaction will generally depend on your individual sensitivity, the amount of sap that came into contact with your skin and which body parts were actually exposed.
Symptoms
The first symptom you will notice is an itching sensation usually accompanied by redness, swelling or blisters. The blisters may also rupture, leak or become covered with scabs. In most cases, these symptoms disappear by themselves within 7 to 10 days. Healing more severe reactions however can require more than 3 weeks.
Consult a doctor if your child exhibits the following symptoms:
- Gets a rash covering a large area of skin or touching the face, eyes and genitals
- A rash that doesn’t improve after you start first aid
- A fever, red streaks or develops an increased sensitivity and redness
- Develops severe swelling caused by the eruption
- Symptoms worsen rapidly
Treatment
The first thing you can do is wash all the exposed areas including under the nails in cold water immediately to avoid prolonged contact of the allergen on your skin. Tecnu is a skin cleanser formulated to remove the oils that cause eruptions and itching in addition to preventing the spread of irritants and this product is a good alternative to soap, which tends to temporarily remove the natural protective layer that prevents urushiol from penetrating your skin. Also wash clothes, contaminated objects and pets with water and soap if they have touched poison ivy.
To help you manage the itch that often accompany the rash, you can try applying cold compresses or compresses soaked in a solution made with baking soda. Oatmeal baths may also soothe your skin and some prescription drugs such as Benadryl, Calamine lotion or a topical cortisone preparation like Cortaid will also help relieve itching.
Sources: The Green Pages of the Montreal Botanical Garden, Health-Canada, Santé Canoé, The Montreal Children’s Hospital.
