Poison Ivy

A Poison Ivy rash and Poison Oak rashes are caused by an allergy to the juices of these plants – called Rhus plants. To get the rash, the juice of the plant has to reach your skin, which can be done directly by touching the plant and indirectly via contact with clothing or a pet that carries the plant juice. The only way to prevent a poison ivy rash is to avoid ivy and oak plants, as well as other substances that may have been in contact with the plant’s toxin.
Like other allergies, a Rhus allergy is acquired. While there are some people who never become allergic to Rhus plants, most individuals become sensitized at some point and remain allergic. Once an individual is sensitized to Rhus plants, it is difficult to become desensitized. This process is most commonly performed by an allergist, but is rarely used except in extreme cases.