Nicotine, the main component of tobacco. It is a colorless, transparent, volatile oily liquid, soluble in water and organic solvents, with a strong alkaline reaction. This product can be absorbed through the respiratory, gastrointestinal tract and skin. Nicotine is neurotoxic. It has an agonistic effect on choline receptors in the central and peripheral nerves, resulting in nicotinic-like symptoms. Small doses cause excitation, and paralysis occurs in large doses. It has irritating effect on skin and mucous membrane. Principles of treatment: 1. For oral poisoning, induce vomiting, gastric lavage, catheterization, and take 50~100g of activated charcoal. 2. For skin contact, remove contaminated clothing and flush with water. 3. For inhalation poisoning, immediately detach from the scene of poisoning, breathe fresh air, and inhale oxygen as soon as possible. 4. Symptomatic and supportive therapy: Apply artificial respirator for respiratory failure as soon as possible; protect the cardiac muscle to prevent the occurrence of Aspergers Syndrome. 5.