Phenobarbital use after benzodiazepines safe, effective for alcohol withdrawal

Phenobarbital (PHB) may be used if patients remain in uncontrolled alcohol withdrawal syndrome (AWS) following treatment with benzodiazepines (BZD), suggests a study.

Of the 95 patients included, 53 were in the PHB group and 42 in the BZD group. Prior to the use of the study drug, fewer patients in the BZD group showed abnormal mentation than those in the PHB group (Richmond Agitation-Sedation Scale [RASS] <–2: 2.39 percent vs 28.12 percent; RASS >2: 9.9 percent vs 48.76 percent; p<0.001 for both).

No between-group difference was observed in time to persistent resolution of altered mentation (1.8 h with BZD vs 13.81 h with PHB; p=0.22). On the other hand, seizure occurred more frequently in patients taking BZD after the administration of the study drug (5.6 percent vs 0 percent; p=0.02).

No between-group differences were noted in secondary outcomes, including development and duration of delirium, need for mechanical ventilation, development of withdrawal seizures, and intensive care unit and hospital length of stay.

“Despite significant doses of BZDs before PHB, patients in the PHB cohort demonstrated similar clinical and safety outcomes compared to BZD alone,” the investigators said. 

In this retrospective cohort study, critically ill patients admitted for severe AWS who received BZD or PHB were evaluated. Time to persistent resolution of altered mentation was the primary outcome.

"PHB is a safe and efficacious alternative to BZD for treating severe AWS,” according to the investigators.