Triggered by Triggered by poison ivy, poson oak, or sumac 2023-01-18T07:23:05Z Applies to a sign or symptom that is provoked or brought about by exposure (cutaneous contact) to poison ivy, poison oak, and poison sumac. These three plants each contain urushiol. Contact with these plants is the most common causes of clinically diagnosed allergic contact dermatitis. Contact with poison ivy, poison oak, or sumac