Editorial Director, Addiction & Recovery · Last reviewed January 2025
Alcohol use disorder (AUD) is the most prevalent substance use disorder in the United States. The 2021 NSDUH found that approximately 29.5 million Americans aged 12 or older had AUD in the past year. Despite this prevalence, only approximately 7.6% received treatment. AUD spans a severity spectrum from mild to severe and is associated with significant medical, psychiatric, and social consequences.
DSM-5 Criteria
AUD is diagnosed when two or more of eleven criteria are met within a 12-month period. Criteria include: drinking more than intended, inability to cut down, spending significant time obtaining or recovering from alcohol, craving, failure to fulfill role obligations, continued use despite social problems, giving up activities, use in hazardous situations, continued use despite physical or psychological problems, tolerance, and withdrawal.
The Neurobiology of Alcohol Dependence
Alcohol modulates GABA (inhibitory) and glutamate (excitatory) neurotransmission. Chronic heavy use causes neuroadaptation — GABA receptors downregulate and NMDA glutamate receptors upregulate — producing a state of CNS hyperexcitability that underlies the withdrawal syndrome. Chronic alcohol use also reduces serotonin activity, contributing to the high rates of depression in AUD.
Alcohol Withdrawal
Alcohol withdrawal can be medically dangerous. Mild withdrawal produces anxiety, tremor, diaphoresis, and insomnia beginning 6–24 hours after the last drink. Moderate withdrawal can produce seizures (typically 12–48 hours after last use). Severe withdrawal — delirium tremens (DTs) — involves confusion, fever, tachycardia, and autonomic instability and can be life-threatening without treatment. Medical management with benzodiazepines (CIWA-guided protocol) or phenobarbital is the standard of care for significant alcohol withdrawal.
Medical Consequences of Chronic Alcohol Use
Chronic heavy alcohol use affects virtually every organ system. Major consequences include: alcoholic liver disease (fatty liver, alcoholic hepatitis, cirrhosis), Wernicke-Korsakoff syndrome from thiamine deficiency, alcoholic cardiomyopathy, peripheral neuropathy, pancreatitis, and elevated risk for multiple cancers including liver, esophageal, and breast cancer. Alcohol is classified as a Group 1 carcinogen by the International Agency for Research on Cancer.
Evidence-Based Treatment
Medications: Naltrexone (oral or extended-release injectable) reduces alcohol craving and the pleasurable effects of alcohol — multiple RCTs demonstrate significant reductions in heavy drinking days and relapse rates. Acamprosate normalizes the glutamate hyperexcitability of alcohol withdrawal and is most effective for maintaining abstinence after detoxification. Disulfiram is a third-line option requiring high patient motivation and ideally supervised administration.
Behavioral treatments: CBT, Motivational Enhancement Therapy (MET), Behavioral Couples Therapy (BCT for those in relationships), and 12-step facilitation all have evidence bases for AUD. Brief interventions by primary care providers have demonstrated efficacy for hazardous drinking that has not yet reached disorder severity.
Related: Alcohol & Mental Health · MAT Overview · Depression & Addiction