What Is a Substance Use Disorder (SUD)?

As far back as 1956, the American Medical Association (AMA) recognized addiction to alcohol and other drugs as a chronic disease. More recently, the National Institute on Drug Abuse (NIDA) defined addiction in part as a “disorder characterized by compulsive drug seeking and use despite adverse consequences.”

Addiction, or substance use disorder, as it’s also known, is referred to as a brain disorder because it causes long-lasting chemical changes in the brain. Every drug has some unique effects on people, but many of the symptoms of substance use disorder are the same no matter what drug is used. The changes substance use disorder causes in the brain and the rest of the body are the source of the negative symptoms people experience. With continued substance use, these symptoms worsen; if left untreated, addiction can be fatal.

Many people think quitting alcohol or other drugs is a question of willpower. This is not true; it’s a myth, and it keeps people from seeking help. Addiction is a disease, not a moral failing or a lack of willpower. The concept of substance use disorder as a medical disease—something beyond one’s control like asthma or diabetes—can help people realize that they should seek help for it, just as they would seek help for other medical diseases.

Scientists are learning more and more about substance use disorders and what happens to the brain when someone develops an addiction, but there’s still a lot they don’t know. For example, they can’t predict how many times alcohol or other drugs must be used before a person develops a substance use disorder. A person’s unique genetic makeup, family life, and social environment all play a role. What we do know is that anyone who uses illicit drugs or misuses alcohol is taking a risk for harm to themselves or others, including overdose, car accidents, psychological problems, and development of a substance use disorder. In the end, if addiction occurs, it is extremely painful and difficult to quit, regardless of which drug is taken—but it can be done.

Like diabetes, asthma, or other medical diseases, substance use disorder can be treated and managed. Treatment can involve detoxification (getting drugs out of one’s system); taking medications under the supervision of a doctor; and having individual or group therapy in an outpatient, hospital, or residential setting. Sometimes people seek treatment voluntarily. Sometimes they are ordered into treatment by the court or directed by an intervention from family members or friends. In either case, research shows that people can benefit from treatment regardless of their reasons for entering it.

What Causes Substance Use Disorder?There are a number of causes of substance use disorders. Here are some of the general ones, but many pieces make up the puzzle of addiction:

Genetics. Addiction can run in families.
Trauma/environmental issues. Experiencing physical or emotional abuse at home, school, and elsewhere or feeling abandoned by parents or guardians can increase a person’s risk of developing a substance use disorder.
The age at which a person starts drinking or using other drugs. The earlier someone uses a substance, the more likely they are to develop a substance use disorder.
Co-occurring disorders. Some people with an undiagnosed or untreated mental health disorder, such as depression or an anxiety disorder, may self-medicate their symptoms, which can lead to addiction.

The Daily Pledge is a free, online social community, made possible by the Hazelden Betty Ford Institute for Recovery Advocacy, that provides a source of support and fellowship to those touched by or concerned about the disease of addiction. The Daily Pledge provides healthy daily activities on the home page, which are viewable to all who might benefit from seeing others "recover out loud." This community's members include both people with addiction and family and friends of people with addiction. Our experience is that people with diverse experiences are able to help each other in unique and valuable ways. Learn more about the community by exploring the pages linked in the menu.