Different drugs affect the body in different ways. The brain and body have a normal way of functioning on a day-to-day basis, and there are very specific patterns that regulate how the brain and central nervous system work together for healthy living. Any type of chemical suddenly introduced to the body disrupts the chemical messengers in the brain, sending different signals to the body. This is why individuals see, think and act differently than they normally behave when they are under the influence of drugs and alcohol.
The medical community acknowledges that addiction is a chronic disease, characterized by one’s inability to stop the behavior of using, even in the presence of negative consequences. Some people refer to this as the “phenomenon of craving.”
Repeated drug use will overload the brain with dopamine. Dopamine is the chemical in the brain that causes the user to feel euphoric. This overload makes it difficult for users to refrain from abusing substances, even though they may desperately desire to do so. Over time, the large amounts of dopamine flooding the brain limits its natural ability to produce the chemical without the use of substances. This results in the addicted no longer being able to take pleasure in the activities that give pleasure in a natural and healthy way. Psychologists refer to this process as habituation. This term is defined by psychologists as “the diminishing of a physiological or emotional response to a frequently repeated stimulus.”