Substance Use Disorder is defined by NIDA and SAMHSA

NIDA (National Institute on Drug Abuse) Definition of SUD/Addiction

What is drug addiction?

Addiction is defined as a chronic, relapsing disorder characterized by compulsive drug seeking, continued use despite harmful consequences, and long-lasting changes in the brain. It is considered both a complex brain disorder and a mental illness. Addiction is the most severe form of a full spectrum of substance use disorders, and is a medical illness caused by repeated misuse of a substance or substances.

Why study drug use and addiction?

Use of and addiction to alcohol, nicotine, and illicit drugs cost the Nation more than $740 billion a year related to healthcare, crime, and lost productivity. In 2016, drug overdoses killed over 63,000 people in America, while 88,000 died from excessive alcohol use. Tobacco is linked to an estimated 480,000 deaths per year. (Hereafter, unless otherwise specified, drugs refer to all of these substances.)

How are substance use disorders categorized?

NIDA uses the term addiction to describe compulsive drug seeking despite negative consequences. However, addiction is not a specific diagnosis in the fifth edition of The Diagnostic and Statistical Manual of Mental Disorders (DSM-5)—a diagnostic manual for clinicians that contains descriptions and symptoms of all mental disorders classified by the American Psychiatric Association (APA).

In 2013, APA updated the DSM-5 by replacing the categories of substance abuse and substance dependence with a single category: substance use disorder. Substance use disorders are measured on a continuum from mild to severe.

SAMHSA (Substance Abuse and Mental Health Services Administration) Definition

SAMHSA defines a mental and/or substance use disorder as occurring when the recurrent use of alcohol and/or drugs causes clinically significant impairment, including health problems, disability, and failure to meet major responsibilities at work, school, or home.

Impairment and Diagnosis

Mental and substance use disorders can affect a person’s ability to think, feel, and make choices. Reaching a level that can be formally diagnosed often depends on a reduction in a person’s ability to function as a result of the disorder. For example:

• Serious Mental Illness (SMI): Defined by someone over 18 having (within the past year) a diagnosable mental, behavioral, or emotional disorder that causes serious functional impairment that substantially interferes with or limits one or more major life activities.
• Serious Emotional Disturbance (SED): For people under the age of 18, this refers to a diagnosable mental, behavioral, or emotional disorder in the past year, which resulted in functional impairment that substantially interferes with or limits the child’s role or functioning in family, school, or community activities.
• Substance Use Disorders (SUD): Occur when the recurrent use of alcohol and/or drugs causes clinically significant impairment, including health problems, disability, and failure to meet major responsibilities at work, school, or home.

Co-occurring Disorders

The coexistence of both a mental health disorder and a substance use disorder is referred to as co-occurring disorders. The National Institute for Mental Health’s Mental Health Information page has information about specific conditions and disorders as well as their symptoms.

SAMHSA’s Mission

SAMHSA’s mission is to reduce the impact of mental and substance use disorders on America’s communities. SAMHSA works to prevent and treat mental and substance use disorders and provide support for people seeking or already in recovery.