Many people struggle with understanding why or how people become addicted to substances. It is often mistakenly assumed that the substance user lacks moral principles, will-power, or self-control and that they could stop using by simply choosing to. In reality, drug addiction is a complex brain disease that takes more than good intentions and a strong will to overcome.
Definition of Addiction: An addiction or substance use disorder is defined as a chronic, relapsing brain disease that is characterized by compulsive drug-seeking and use despite negative and harmful consequences not only to the substance user, but to those around him/her. It is considered a disease because drugs change the structure of the brain and how it works. These brain changes can be long lasting and can lead to many harmful and often self-destructive behaviors.
Reasons why people use drugs: While there are a variety of different reasons why people use substances, the most commonly reported reasons are 1.) To feel good, 2.) To feel better, 3.) To do better, and 4.) Curiosity or because others are doing it. Initially the use of a substance may not be problematic, but over time and with continued use, a person needs more of the substance to not only feel good, feel better, or do better, but to feel normal. Seeking out the drug becomes a compulsive act with dire consequences such as incarceration, loss of relationships, financial strain and death. It is important to note that while the initial decision to use a substance is most often voluntary, the compulsion and inability to exert self-control leading to substance dependence is not. Brain scans of people diagnosed with substance use disorders show physical changes in the areas of the brain critical to judgment, decision making, learning and memory, and behavior control.
Factors that increase the risk of addiction: There is no single factor that can predict if a person will become addicted to a substance. Addiction is a bio-psycho-social disease, which means that the interaction of a number of factors, biological; psychological; and social factors play a role in determining if a person will develop the disease of addiction or not. These factors are explained below.
Biological: Scientists estimate that genetics account for 40% to 60% of a person's vulnerability to addiction. Drug abuse often runs on families; however while having parents that abuse substances puts a child at risk, it is possible for a child to grow up without substance dependence. It is also A person's stage of development and/or other medical condition(s) also plays a role.
Psychological: Substance abuse and dependence often occur alongside other conditions like mental illness. While having a mental health condition alone is not thought to cause substance dependence, having one complicates the other. Some people with mental health conditions may attempt to manage their underlying mental health symptoms by using substances (self-medication). A person's behavior, personality and mood such as emotional turmoil, negative thinking, and lack of self-esteem and confidence are also factors that may result in a higher risk towards developing a substance use disorder.
Social: A person's environment includes a number of different influences that may increase a person's risk for addiction. The influence of the home, especially during childhood, is a very important factor. A chaotic home life, being abused or neglected as a child and exposure to parental or other adult substance use increases a child's risk. Friends and acquaintances can have an increasingly strong influence, especially during adolescence. Substance using peers can sway even those without risk factors to try drugs for the first time. Academic failure and/or poor social skills also increases risk.
Other factors that increase the risk for a substance use disorder include the age in which a substance is first used, and the method of administration. Although taking drugs at any age can lead to addiction, research shows that the earlier a person begins to use durgs, the more likely they are to develop serious problems. This is due to the harmful effects that drugs can have on the developing brain. Smoking a drug or injecting it increases addictive potential as well. When a substance is smoked or injected, it enters the brain within seconds, producing a powerful rush of pleasure. However, this intense euphoria can fade within a few minutes resulting in a stronger drive to repeat the behavior to achieve this fleeting pleasurable state.
*See the next section, 'Addiction and the Brain' for information about how and why the use of substances over time impacts the brain resulting in changes in the chemical structure of the brain.