Abstract
Alcohol use disorder (AUD) represents a critical public health challenge, with early-life adversity conferring heightened risk for compulsive drinking patterns. Alcohol has long been known to exert direct effects on developing neurotransmitter systems, targeting among others GABAergic, glutamatergic, and dopaminergic signaling. Recent evidence however indicates that early adversity also primes microglial activation and establishes chronic low-grade neuroinflammation, disrupting maturation of prefrontal-limbic-striatal circuits governing executive control and affect regulation. Hence, alcohol use may emerge in adolescents as a maladaptive coping mechanism, transiently alleviating stress-related dysphoria while exacerbating neuroimmune and neurocircuit dysfunction. While traditional neurocentric models convincingly depict how repeated withdrawal episodes may unmask this underlying vulnerability, precipitating relapse cycles that consolidate compulsive use, they inadequately explain the persistence and treatment resistance characteristic of adolescent-onset alcohol misuse because they fail to account for the peripheral biological systems that amplify central vulnerability. The gut-microbiota-brain axis represents one such amplifier: stress- and alcohol-related perturbations in barrier integrity and immunometabolic signaling increase peripheral inflammatory load reaching the brain, intensifying neuroimmune tuning of still-maturing control circuits. Integrating these central and peripheral processes reframes adolescent alcohol vulnerability as a systems-level phenomenon embedded within developmental and inflammatory biology, rather than a disorder of reward circuitry alone. This developmental framework suggests that adjunctive therapeutic strategies combining targeted neuroimmune modulation, behavioral intervention, and ecological stabilization during critical developmental windows may offer superior outcomes over conventional reward-focused pharmacotherapies. Realizing this potential will require biomarker-driven risk stratification, precision medicine approaches, and careful developmental consideration of intervention timing.