Someone who abuses cocaine normally enjoys a brief spike of euphoria. It acts as a stimulant and triggers the release of dopamine, the body's natural feel-good hormone. When the effects of cocaine fade off, a collapse occurs, during which users often feel extremely miserable or depressed. Adaptation to the drug builds with time, and increasing amounts of cocaine are necessary to get the same pleasurable feeling. However, continuous use of cocaine might result in a decrease in the brain's natural production of dopamine. This impairs the user's ability to experience pleasure in the absence of cocaine and may result at the beginning of major depressive disorder. Depression is caused by an imbalance of neurochemicals in the brain, which can emerge as a result of long-term frequent cocaine usage.