Poison ivy. Just the mention of the dreaded three-leafed plant can make anyone start to itch and scratch. It's a common wild plant that causes an extremely irritating allergic reaction when touched or brushed against. The leaves, stems and roots of poison ivy contain a resin called urushiol. Even the slightest exposure to skin can trigger an immediate inflammation or allergic reaction. In severe cases, this rash can develop into very painful, swollen areas of skin filled with fluid.

A poison ivy rash usually appears within two days of exposure, peaks after five days and begins to fade after a week to ten days. And poison ivy isn't the only leafy landmine to watch out for. It's two rather nasty relatives, poison oak and poison sumac, cause similar discomfort.

Most cases of the rash can be self-treated using calamine lotion or over the counter ointments and creams containing zinc oxide. Apply cold compresses for 15 to 30 minutes at a time, several times daily. That will help relieve the itching and blistering. A paste made up of baking soda and water can also be applied to the rash. An oatmeal bath provides relief as well.

Anyone with complications from a severe case of poison ivy, or with a rash that is not improving with self-treatment, needs to see a doctor. The best way to deal with poison ivy, and its relatives, is to learn to recognize the plants – then stay away from them. If you suspect contact with a poison ivy plant, wash immediately and thoroughly with soap and water. Clean all shoes, clothes and tools that might have come in contact with any of the plant resin.

Finally, the old folk tale about eating poison ivy leaves to become immune, is just that. Never eat the berries or leaves of wild plants.

For more information on allergies, please visit :

• HealthyOntario.com

July 2003

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