Undertreatment of Wernicke encephalopathy in alcohol-related clinical contexts: a scoping review of diagnosis, thiamine regimens, and clinical management

Background Wernicke encephalopathy (WE) is a potentially reversible neurological emergency that remains frequently missed and undertreated in patients with alcohol use disorder (AUD). Although thiamine is widely accepted as the cornerstone of prevention and treatment, diagnostic uncertainty, limited comparative evidence, and heterogeneous clinical recommendations contribute to substantial variability in real-world management. This scoping review aimed to map the available evidence on the diagnosis and clinical management of WE in patients with AUD or clinically significant alcohol use, with particular attention to practice variability, undertreatment, and clinically actionable gaps in care. Methods We conducted a scoping review in accordance with PRISMA-ScR guidance. Electronic databases and trial registries were searched for studies addressing the diagnosis, prevention, or treatment of WE in populations with AUD or clinically significant alcohol use. Eligible sources included randomized controlled trials, observational studies, clinical audits, and implementation-focused reports. Data were charted and synthesized thematically. Results A total of 26 studies were included. The evidence base was limited and heterogeneous. Only two randomized controlled trials evaluated thiamine regimens, and no consensus emerged regarding optimal dosing. Diagnostic criteria for WE varied widely across studies, with inconsistent use of formal criteria such as the Caine criteria. Across observational studies and prescribing audits, undertreatment was consistently reported, including delayed initiation of therapy and frequent use of oral thiamine in high-risk scenarios. Studies describing more protocolized and guideline-concordant care more often reported earlier treatment initiation and use of parenteral thiamine in suspected or confirmed cases. Conclusions WE remains underrecognized and undertreated in AUD and clinically significant alcohol use. The mapped evidence suggests that diagnostic uncertainty, limited trial data, and inconsistent implementation of recommendations are associated with persistent variability in care. Although the optimal thiamine regimen remains unresolved, early recognition and appropriate parenteral treatment in high-risk or suspected cases represent actionable opportunities to reduce preventable neurological morbidity.