Addiction occurs when taking a substance or engaging in an activity becomes a compulsion. The person loses the ability to stop the behavior, no matter the harm it causes. Addiction comes in different forms. Types of addictions range from substance like alcohol and drugs (substance use disorders) to behaviors like a gambling disorder. Addictions can cause people to lose their loved ones, jobs, their status in communities and even their lives. It can have harmful effects on other people. But behind each addiction is a person who is struggling with a chronic medical illness. Because addictions can have such harmful effects on people’s lives, there is also an urgency to understand how to best help people fight them.
There is no one cause of addiction. From a public health perspective, addiction involves three causes interacting with each other—the agent, which is the drug itself, characteristics of the person with addiction and his or her environment.
There is a common misconception that addiction is the result of someone having moral failing—being “weak” or lacking willpower. Research has shown that addiction is a complex, chronic illness that affects the brain and body, just like heart disease and diabetes. It changes both the brain’s structure and how it works. The brain’s circuit of reward, motivation, memory, impulse control and judgment shifts from recognizing something as pleasurable to seeking it out compulsively. The memory of the desired response continues, and people behave in a way that satisfies the need to recreate the memory. Over time, the brain needs more and more of the drug to achieve the desired response. People can cycle through periods of remission and relapse. Without treatment or an improvement in the brain-reward cycle, the effects of addiction can even progress to premature death.