Because crack is smoked, and allows high doses to reach the brain rapidly, crack is even more addictive. Both forms of the drug trap a chemical called dopamine in the spaces between the brain's nerve cells in a part of the brain called the reward system. Dopamine stimulates and restimulates these nerve cells, making the user feel intense pleasure. The brain responds to the overabundance of dopamine by destroying some of it, making less of it, and shutting down the cells' receptors so they can no longer receive dopamine's messages. Addicts are preoccupied with getting their drug, and most of their thoughts and behaviors are directed to that end.
Cocaine interferes with judgment and produces exaggerated feelings of well-being and confidence.
High doses can produce paranoia, and users can become aggressive and violent. In rare cases, cocaine can produce death, after first use or after prolonged use. Pregnant mothers should never use any drug during pregnancy. Scientists are trying to understand the precise effect of cocaine on the developing fetus. They know that a mother who is addicted to drugs does not take care of herself properly, that her fetus does not receive adequate nutrition needed to develop properly, and that addicted mothers rarely can care for their newborns properly.