Poison ivy rash is caused by the contact with any part of the poison ivy plant. This rash is also often called “urushiol-induced dermatitis”, since such a reaction develops due to contact with a highly toxic substance called urushiol. Urushiol is found in plants of the same family and includes: poison ivy, poison oak and poison sumac.
The most common way to come in contact with a plant from this family is while walking, hiking, or biking in the woods. There are many people who do not know what the poison ivy plant looks like, and they may touch it inadvertently, while they are walking somewhere in a wooded area. However, many homeowners may become subjected to contact with poison ivy in their very own yards, and even in their well maintained flower beds. Poison ivy nowadays is spread more abundantly throughout the U.S.A, Southern Canada and Northern Mexico than it used to be centuries ago, due to the development of real estate in nearby wooded areas.
Poison ivy rash generally appears within 12-48 hours after the contact with the plant or any other carrier of the poison ivy’s urushiol (clothes, garden tools, pet hair, etc). People who are hypersensitive to urushiol may even show the signs of this dermatitis within a half-an-hour after contact.
A poison ivy rash may look like raised colorless bumps, reddish areas, or even yellowish watery blisters of varying sizes. Large blisters often ooze, and then cover with crusts as they dry up. The rash often covers a linear area on the body, such as if a person brushed against the poison ivy vine while walking along a weedy path. However, in many cases the rash may cover extensive and irregular areas of the skin, especially if the person had urushiol on their hands or their clothes, which then got onto different areas of their skin.
Poison ivy rash does not just appear on the skin of people. It may also develop in the throat, in the airways, and on the lining of the lungs. These locations of the rash may even lead to fatal outcomes in the worst cases. Generally, this type of reaction follows someone inhaling the smoke from the fire where poison ivy is being burned. In extremely rare cases of the plant’s digestion, people also develop horrific consequences in the form of throat and stomach lining burns.
A very sensitive person may even develop the poison ivy rash merely by walking or biking near where someone is taking down poison ivy plants with a lawn mower or a trimmer, which is known as airborne urushiol contact.