Alcohol misuse: Drinking in a manner, situation, amount, or frequency that could cause harm to the person who drinks or to those around them. For individuals younger than the U.S. Minimum Legal Drinking Age of 21, or for pregnant females, any alcohol use constitutes alcohol misuse.

Alcohol use disorder (AUD): AUD is a chronic, relapsing brain disorder characterized by an impaired ability to stop or control alcohol use despite adverse social, occupational, or health consequences. AUD can range from mild to severe, and recovery is possible regardless of severity. The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), published by the American Psychiatric Association, described two distinct disorders—alcohol abuse and alcohol dependence—with specific criteria for each. The fifth edition, DSM-5, integrates the two DSM-IV disorders, alcohol abuse and alcohol dependence, into a single disorder called alcohol use disorder, or AUD, with mild, moderate, and severe subclassifications.

Alcohol-impaired driving fatality: A fatality in a crash involving a driver or motorcycle rider (operator) with a blood alcohol concentration (BAC) of 0.08 g/dL or more (a BAC of 0.08% corresponds to 0.08 grams of alcohol per deciliter, or 0.08 grams per 100 milliliters).

Binge drinking:

• The National Institute on Alcohol Abuse and Alcoholism (NIAAA) defines binge drinking as a pattern of drinking alcohol that brings blood alcohol concentration (BAC) to 0.08%—or 0.08 grams of alcohol per deciliter—or more. This typically happens if a woman has four or more drinks, or a man has five or more drinks, within about two hours.¹
• The Substance Abuse and Mental Health Services Administration (SAMHSA), which conducts the annual National Survey on Drug Use and Health (NSDUH), defines binge drinking as consuming five or more beverages containing alcohol for males or four or more beverages containing alcohol for females on the same occasion (i.e., at the same time or within a couple of hours of each other) on at least one day in the past 30 days, regardless of frequency in the past year.² 
• The Monitoring the Future (MTF) survey defines binge drinking as having five or more drinks in a row in the past two weeks.³ 

Disability-adjusted life years: A measure of years of life lost or lived in less than full health.

Heavy alcohol use (or heavy drinking):

• NIAAA defines heavy alcohol use as follows:
  • For men, consuming five or more drinks on any day or 15 or more per week
  • For women, consuming four or more drinks on any day or eight or more per week
• SAMHSA defines heavy alcohol use for males as drinking five or more drinks on the same occasion (i.e., at the same time or within a couple of hours of each other) and for females as drinking four or more drinks on the same occasion on each of 5 or more days in the past 30 days.²

High-intensity drinking:

• Consumption of two or more times the gender-specific thresholds for binge drinking, which means 10 or more standard drinks (or alcoholic drink equivalents) for males and eight or more for females. High-intensity drinking is consistent with drinking at binge levels II and III. The levels correspond to one to two times (I), two to three times (II), and three or more times (III) the standard gender-specific binge thresholds.⁴
• The MTF survey defines high-intensity drinking among adolescents as consuming 10 or more (8th, 10th, and 12th grade) or 15 or more (12th grade only) drinks in a row in the past 2 weeks.³

Medication assisted treatment (MAT) for AUD: The 2023 NSDUH defines MAT as medication prescribed by a doctor or other health professional to help cut back or stop the use of alcohol. Medications shown to survey respondents as examples included acamprosate, disulfiram, naltrexone pills, and injectable naltrexone.²

Patterns of drinking associated with AUD: Binge drinking and heavy alcohol use can increase an individual’s risk of AUD. According to the 2020–2025 Dietary Guidelines for Americans, adults of legal drinking age can choose not to drink or to limit intake to two drinks or less in a day for men and one drink or less in a day for women, when alcohol is consumed. Drinking less is better for health than drinking more. Some individuals should avoid alcohol completely.

Substance use treatment: The 2023 NSDUH defines substance use treatment as treatment in an inpatient location, in an outpatient location, via telehealth, or in a prison, jail, or juvenile detention center or MAT for alcohol use or opioid use.²

Underage drinking: Alcohol use by anyone under the age of 21. The U.S. Minimum Legal Drinking Age is 21.