Objective: Patients with severe alcohol withdrawal and delirium tremens are frequently resistant to standard doses of benzodiazepines. Case reports suggest that these patients have a high incidence of requiring intensive care and many require mechanical ventilation. However, few data exist on treatment strategies and outcomes for these subjects in the medical intensive care unit (ICU). Our goal was a) to describe the outcomes of patients admitted to the medical ICU solely for treatment of severe alcohol withdrawal and b) to determine whether a strategy of escalating doses of benzodiazepines in combination with phenobarbital would improve outcomes. Design: Retrospective cohort study. Setting: Inner-city municipal hospital. Patients: Subjects admitted to the medical ICU solely for the treatment of severe alcohol withdrawal. Interventions: Institution of guidelines emphasizing escalating doses of diazepam in combination with phenobarbital. Measurements and Main Results: Preguideline (n = 54) all subjects were treated with intermittent boluses of diazepam with an average total and maximal individual dose of 248 mg and 32 mg, respectively; 17% were treated with phenobarbital. Forty-seven percent required intubation due to inability to achieve adequate sedation and need for constant infusion of sedative-hypnotics. Intubated subjects had longer length of stay (5.6 vs. 3.4 days; p = .09) and higher incidence of nosocomial pneumonia (42 vs. 21% p = .08). Postguideline (n = 41) there were increases in maximum individual dose of diazepam (32 vs. 86 mg; p = .001), total amount of diazepam (248 vs. 562 mg; p = .001), and phenobarbital use (17 vs. 58%; p = .01). This was associated with a reduction in the need for mechanical ventilation (47 vs. 22%; p = .008), with trends toward reductions in ICU length of stay and nosocomial pneumonia. Conclusions: Patients admitted to a medical ICU solely for treatment of severe alcohol withdrawal have a high incidence of requiring mechanical ventilation. Guidelines emphasizing escalating bolus doses of diazepam, and barbiturates if necessary, significantly reduced the need for mechanical ventilation and showed trends toward reductions in ICU length of stay and nosocomial infections. (C) 2007 by the Society of Critical Care Medicine and Lippincott Williams & Wilkins