Nicotine polacrilex, commonly known as nicotine gum, is a pharmaceutical formulation used for nicotine replacement therapy (NRT) to aid in smoking cessation. Its structure consists of nicotine bound to a resin known as polacrilex, which serves as a delivery system for controlled release of nicotine. This structure allows nicotine to be slowly released and absorbed through the lining of the mouth when the gum is chewed. The polacrilex resin helps to minimize the harshness of nicotine and reduce its rapid absorption into the bloodstream, thereby reducing withdrawal symptoms and cravings associated with smoking cessation. This makes nicotine polacrilex an effective tool for individuals trying to quit smoking.