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Poison Ivy
Overview

Poison ivy is an allergic reaction caused by exposure to plants in the “Toxicodendron” family. The resultant skin lesions are due to the “poisonous” portion of the plant, urushiol. The poison ivy plant is recognized by its three leaflets which contain within them urushiol oil. The side effects of urushiol are manifested only when it comes in contact with skin. Thus a whole, undamaged plant will not be harmful. However, the leaves can be harmed easily and are dangerous even if the plant is no longer alive, so it should be avoided. Poison ivy is found all over America and depending on the location may be growing as a vine or a shrub.

Signs and Symptoms

Signs and Symptoms

The symptomatology is based on the body’s immune reaction to a poisonous substance. The oxidized oil bind to proteins in skin cells and makes them seem foreign to the body’s immune system. Immune cells subsequently attack these cells which causes the characteristic symptoms of redness along with intense itching. Raised lesions form on the skin and some may be filled with fluid. The area of the skin that has come in contact with the plant has a linear appearance. The affected area of the skin has lesions appearing at different times making it look like the disease is spreading. The reason for this is the variation in urushiol exposure to the diseased skin.

Diagnosis of Poison Ivy

Diagnosis of Poison Ivy

This is based on taking a thorough history and performing a physical examination. The history will reveal the patient having had exposure to the plant whether in the woods or another location. The characteristic lesions also aid in reaching the final diagnosis.

Treatment of Poison Ivy

Treatment of Poison Ivy

To relieve symptoms of itching topical ointments like calamine lotion, which has been shown to have anti- itch properties, is used. Patients also found relief from oatmeal baths, which can be made from ingredients found at home or over the counter products. Oral antihistamines can be taken if topical lotions are not sufficient. Depending on the severity of the reaction topical and systemic steroids may be required. Constant itching can cause skin abrasions in which bacteria enter and induce a secondary infection. For any such condition treatment with antibiotics is also started. To prevent the spread of poison ivy to others be sure to immediately wash the affected area with soap and cold water and remove any contaminated clothing.