Abstract
We present a case of phytodermatitis caused by a poisonous plant known as poison ivy. It is one of the leading causes of allergic contact dermatitis and it causes significant morbidity in the United States. Prevention of the disease is by identification and avoidance of the plant. Barrier protection minimises the chance of contact and prompt rinsing with soap water limits antigen exposure after skin contact. General approach to treatment of allergic contact dermatitis can be applied but special precaution should be taken on the duration of systemic steroid therapy. Too short a course of oral steroid may result in a more severe recurrent flare. High potency topical steroids may limit the development of skin lesions. (Hong Kong j.emerg.med. 2011; 18:335-338)