Understanding Addiction
Many people don't understand why or how other people become addicted to drugs. They may mistakenly think that those who use drugs lack moral principles or willpower and that they could stop their drug use simply by choosing to. In reality, drug addiction is a complex disease, and quitting usually takes more than good intentions or a strong will. Drugs change the brain in ways that make quitting hard, even for those who want to. Fortunately, researchers know more than ever about how drugs affect the brain and have found treatments that can help people recover from drug addiction and lead productive lives.
What Is Drug Addiction?
Addiction is a chronic disease characterized by drug seeking and use that is compulsive, or difficult to control, despite harmful consequences. The initial decision to take drugs is voluntary for most people, but repeated drug use can lead to brain changes that challenge an addicted person’s self-control and interfere with their ability to resist intense urges to take drugs. These brain changes can be persistent, which is why drug addiction is considered a "relapsing" disease—people in recovery from drug use disorders are at increased risk for returning to drug use even after years of not taking the drug.
It's common for a person to relapse, but relapse doesn't mean that treatment doesn’t work. As with other chronic health conditions, treatment should be ongoing and should be adjusted based on how the patient responds. Treatment plans need to be reviewed often and modified to fit the patient’s changing needs.
Why are Drugs so Hard to Quit?
Addiction and substance use disorders are often misunderstood. Some people believe continuing to use drugs even when they cause harm is a sign of weakness or poor character—but that’s far from the truth.
Many years of research show that substance use disorders are complex, chronic, and treatable medical conditions that involve changes in our brains. Researchers think it works like this:
Our brains have what scientists call a “reward system.” Behaviors that help us survive and stay healthy produce small increases in naturally occurring brain chemicals called “neurotransmitters” in parts of the reward system related to pleasure. That helps explain why biting into a favorite food, seeing someone you love smile, or learning something new can all feel so rewarding.
When we engage in new, rewarding behaviors, the brain also builds connections between that behavior and related “cues,” like sights, sounds, or feelings that remind us of that reward. That’s why just walking by a restaurant that smells good can make us hungry.
And that’s a good thing. This system motivates us to repeat behaviors that help us survive, such as eating, caring for each other, or honing new skills.
Drugs are chemicals that mimic the neurotransmitters of the brain’s reward system—but in many cases, using drugs can affect the reward system more powerfully than other activities.
For some of us, using drugs repeatedly can change the way certain areas of the brain work and communicate with each other. These changes can make it harder to enjoy healthy activities, and people sometimes start to need to use drugs to feel good or okay. Suddenly stopping or significantly reducing regular drug use may even cause withdrawal symptoms that can range from powerful negative emotions to flu-like symptoms to life-threatening emergencies. Many withdrawal symptoms are treatable, though for many, using drugs may feel like the only way to alleviate them.
With repeated drug use, the brain may also build much stronger connections between drugs and cues associated with them—cues that may be difficult to avoid. Some people call these “triggers”—or people, places, things, and feelings that remind a person of using drugs and can make them really want to use them again.
Repeated drug use can also weaken circuits in the brain that help people exercise self-control and tolerate stress. This can make it even more difficult for people to control their drug use—even when it causes harm, when it doesn’t feel the way it used to, or when it gets in the way of other parts of someone’s life.
These can be signs of a substance use disorder.
While certain factors make substance use disorders more likely to occur in some people than in others, anyone can develop a substance use disorder, whatever their race and ethnicity, sex and gender, or economic status.
Addiction can make quitting drugs or controlling drug use very difficult without support—no matter how much someone wants to stop or cut back.
When someone tries to stop using drugs, the strong associations between drugs and related cues and new or ongoing experiences of stress may lead them to experience cravings and use drugs again. Returning to use after stopping, or relapse, is not uncommon. And like addiction itself, it’s not a sign of weakness.
While drugs can change the brain, treatments—and time—can change it too. People can heal from an addiction—especially when they get the support they need to relieve withdrawal symptoms, navigate triggers, and make positive changes. Researchers have developed therapies to support recovery, including safe and effective medications for some substance use disorders like opioid use disorder.
What Happens to the Brain When a Person Takes Drugs?
Most drugs affect the brain's "reward circuit," causing euphoria as well as flooding it with the chemical messenger dopamine. A properly functioning reward system motivates a person to repeat behaviors needed to thrive, such as eating and spending time with loved ones. Surges of dopamine in the reward circuit cause the reinforcement of pleasurable but unhealthy behaviors like taking drugs, leading people to repeat the behavior again and again.
As a person continues to use drugs, the brain adapts by reducing the ability of cells in the reward circuit to respond to it. This reduces the high that the person feels compared to the high they felt when first taking the drug—an effect known as tolerance. They might take more of the drug to try and achieve the same high. These brain adaptations often lead to the person becoming less and less able to derive pleasure from other things they once enjoyed, like food, sex, or social activities.
Long-term use also causes changes in other brain chemical systems and circuits as well, affecting functions that include:
- learning
- judgment
- decision-making
- stress
- memory
- behavior
Despite being aware of these harmful outcomes, many people who use drugs continue to take them, which is the nature of addiction.
Why do Some People Become Addicted to Drugs While Others Don't?
No one factor can predict if a person will become addicted to drugs. A combination of factors influences risk for addiction. The more risk factors a person has, the greater the chance that taking drugs can lead to addiction. For example:
- Biology. The genes that people are born with account for about half of a person's risk for addiction. Gender, ethnicity, and the presence of other mental disorders may also influence risk for drug use and addiction.
- Environment. A person’s environment includes many different influences, from family and friends to economic status and general quality of life. Factors such as peer pressure, physical and sexual abuse, early exposure to drugs, stress, and parental guidance can greatly affect a person’s likelihood of drug use and addiction.
- Development. Genetic and environmental factors interact with critical developmental stages in a person’s life to affect addiction risk. Although taking drugs at any age can lead to addiction, the earlier that drug use begins, the more likely it will progress to addiction. This is particularly problematic for teens. Because areas in their brains that control decision-making, judgment, and self-control are still developing, teens may be especially prone to risky behaviors, including trying drugs.
Can Drug Addiction be Cured or Prevented?
As with most other chronic diseases, such as diabetes, asthma, or heart disease, treatment for drug addiction generally isn’t a cure. However, addiction is treatable and can be successfully managed. People who are recovering from an addiction will be at risk for relapse for years and possibly for their whole lives. Research shows that combining addiction treatment medicines with behavioral therapy ensures the best chance of success for most patients. Treatment approaches tailored to each patient’s drug use patterns and any co-occurring medical, mental, and social problems can lead to continued recovery.
More good news is that drug use and addiction are preventable. Results from NIDA-funded research have shown that prevention programs involving families, schools, communities, and the media are effective for preventing or reducing drug use and addiction. Although personal events and cultural factors affect drug use trends, when young people view drug use as harmful, they tend to decrease their drug taking. Therefore, education and outreach are key in helping people understand the possible risks of drug use. Teachers, parents, and health care providers have crucial roles in educating young people and preventing drug use and addiction.
Points to Remember
- Drug addiction is a chronic disease characterized by drug seeking and use that is compulsive, or difficult to control, despite harmful consequences.
- Brain changes that occur over time with drug use challenge an addicted person’s self-control and interfere with their ability to resist intense urges to take drugs. This is why drug addiction is also a relapsing disease.
- Relapse is the return to drug use after an attempt to stop. Relapse indicates the need for more or different treatment.
- Most drugs affect the brain's reward circuit by flooding it with the chemical messenger dopamine. Surges of dopamine in the reward circuit cause the reinforcement of pleasurable but unhealthy activities, leading people to repeat the behavior again and again.
- Over time, the brain adjusts to the excess dopamine, which reduces the high that the person feels compared to the high they felt when first taking the drug—an effect known as tolerance. They might take more of the drug, trying to achieve the same dopamine high.
- No single factor can predict whether a person will become addicted to drugs. A combination of genetic, environmental, and developmental factors influences risk for addiction. The more risk factors a person has, the greater the chance that taking drugs can lead to addiction.
- Drug addiction is treatable and can be successfully managed.
- More good news is that drug use and addiction are preventable. Teachers, parents, and health care providers have crucial roles in educating young people and preventing drug use and addiction.
Source: National Institute on Drug Abuse (Collected 2023)