Cocaine is a powerfully addictive central nervous system stimulant that can be smoked, injected, rubbed into the gums, or snorted. Crack cocaine is a cheaper form of cocaine that is mixed with ammonia or baking soda and water and then heated. Cocaine has a direct effect on the nervous system, increasing the available amounts of neurotransmitters dopamine, serotonin, norepinephrine, and glutamate, which leads to pleasurable sensations, changes in behavior, and development of addiction with continued use. Addiction does not necessarily develop after an individual's first exposure to cocaine or crack, but thanks to the powerful feelings of euphoria and stimulation, a large number of first-time users go on to continue their use, often to the point of addiction. Cocaine and Crack discusses the nature of cocaine and crack addiction, how it affects one's health, and how it can be treated.