addiction

Addiction is a chronic, relapsing brain disorder characterized by compulsive substance use or engagement in rewarding behaviors despite negative consequences. It involves neuroadaptive changes in reward, motivation and self-control circuits and is influenced by genetic, environmental and developmental factors.

Substance use disorders include dependence on alcohol, opioids, cannabis, stimulants, nicotine, and others. Behavioral addictions (such as gambling) are also recognized; Internet gaming disorder is included in some classifications for further study. Diagnosis typically requires a pattern of use causing significant impairment or distress, with criteria such as craving, loss of control, tolerance, withdrawal, and continued use despite harm.

Causes: risk factors include genetics, early life stress, mental health comorbidity, and social determinants. Neurobiology involves dopamine pathways, stress systems, and learning processes. Relief seeking and reward circuits contribute to compulsive use.

Treatment: evidence-based approaches include pharmacotherapy for certain disorders (e.g., methadone or buprenorphine for opioid use, naltrexone or acamprosate for alcohol, nicotine replacement or varenicline for tobacco) and behavioral therapies (motivational interviewing, cognitive-behavioral therapy, contingency management). Integrated care, family support, and peer-delivered services improve outcomes. Recovery support groups are common adjuncts.

Prognosis and public health: addiction is a chronic condition with risk of relapse, but many achieve long-term recovery with ongoing care. Early intervention and reducing stigma are public health priorities. Prevalence varies by substance and region; comprehensive prevention and treatment reduce morbidity and mortality.