Poison Hemlock Highly poisonous plant endemic to Washington State. How toxic is it? Usually Non Toxic Mildly Toxic Highly Toxic Poison hemlock contains ingredients similar to nicotine and can cause vomiting, seizures, paralysis, and death. Contact Washington Poison Center to assess cases Call 1 (800)-222-1222 Chat with a Poison Specialist Common brands & formats What to do If ingested Keep patient upright. If able to interact, contact Washington Poison Center. If not interacting, call 911 If on skin Wash the affected area as soon as possible with soap and water. Contact Washington Poison Center to assess the situation.