Phenobarbital versus benzodiazepines in alcohol withdrawal syndrome

Aim: Phenobarbital, a long-acting barbiturate, presents an alternative to conventional benzodiazepine treatment for alcohol withdrawal syndrome (AWS). Currently, existing research offers only modest guidance on the safety and effectiveness of phenobarbital in managing AWS in hospital settings. The study objective was to assess if a phenobarbital protocol for the treatment of AWS reduces respiratory complications when compared to a more traditionally used benzodiazepine protocol.

Methods: A retrospective cohort study analyzing adults who received either phenobarbital or benzodiazepine-based treatment for AWS over a 4-year period, 2015-2019, in a community teaching hospital in a large academic medical system.

Results: A total of 147 patient encounters were included (76 phenobarbital and 71 benzodiazepine). Phenobarbital was associated with a significantly decreased risk of respiratory complications, defined by the occurrence of intubation (15/76 phenobarbital [20%] vs. 36/71 benzodiazepine [51%]) and decreased incidence of the requirement of six or greater liters of oxygen when compared with benzodiazepines (10/76 [13%] vs. 28/71 [39%]). There was a significantly higher incidence of pneumonia in benzodiazepine patients (15/76 [20%] vs. 33/71 [47%]). Mode Richmond Agitation Sedation Scale (RASS) scores were more frequently at goal (0 to -1) between 9 and 48 h after the loading dose of study medication for phenobarbital patients. Median hospital and ICU length of stay were significantly shorter for phenobarbital patients when compared with benzodiazepine patients (5 vs. 10 days and 2 vs. 4 days, respectively).

Conclusion: Parenteral phenobarbital loading doses with an oral phenobarbital tapered protocol for AWS resulted in decreased risk of respiratory complications when compared to standard treatment with benzodiazepines.