Giant Hogweed Noxious weed that can cause irritation. How toxic is it? Usually Non Toxic Mildly Toxic Highly Toxic Sap from the giant hogweed sensitizes skin to sunlight resulting in severe burns, blistering, and painful inflammation. Contact the Poison Center for guidance. Call 1 (800)-222-1222 Text 206-526-2121 Chat with a Poison Specialist Common brands & formats What to do Splashed in eye(s) Rinse with water for at least 10 minutes. Wear sunglasses Seek in person healthcare as soon as possible If on skin Remove as much as possible mechanically with paper towel. Wash affected area with soap and water, avoid contaminating other areas. Avoid exposing affected area to light for 48 hours or a week if you have burns. Wear sunscreen.