Plants containing allergens: 1. Poison ivy (skin allergy) Toxicodendron radicans commonly known as poison ivy is a poisonous flowering plant mostly found in North America and in some regions of Asia. This plant may grow as a vine or as an erect shrub. Some other species of this family also contain allergens like poison oak and poison sumac. This plant is known for causing an itching, irritating and painful rash called as urishol-induced-dermatitis or Rhus dermatitis, which is caused by a plant sap or oil called as urushiol. This resinous sap material is composed of catechols with have either a 13 or 15-C side chain. Symptoms The rash produced by coming in contact with the oil or sap of urushiol produces · blisters · severe redness of skin · inflammation · Non-colored b...