Nicotine, commonly known as nicotine, is an alkaloid present in Solanaceae plants (eggplant), an important component of tobacco, or a representative of N-choline receptor agonists. For N1 and N2 receptors and Central nervous system have a role, no clinical application value. Nicotine is addictive or dependent, and repeated use of nicotine also increases heart speed and increases blood pressure and reduces appetite. Large doses of nicotine can cause vomiting and nausea, serious people will die. Tobacco usually contains nicotine.