Background: Previous reviews have examined the use of theoretically supported combinations of drugs for the treatment of alcohol use disorder. This review seeks to examine the strengths and limitations of current clinical evidence for the use of combined pharmacological interventions intended to treat alcohol use disorder.
Objectives: The objective of this review was to identify combinations of pharmacological treatments for alcohol use disorder, and assess the strength of clinical evidence for these treatments.
Methods: We conducted searches using PubMed, EMBASE® through Ovid® (1974 to present), MEDLINE® through Ovid® (1946 to present), and Psychinfo® through Ovid® (1806 to present). Our primary search included the terms "alcoholism" and "drug therapy, combination". Search results were restricted to human subjects and English language. Search criteria were not restricted based on study design or patient age. Studies were evaluated for randomization, blinding, group similarity, power determination, outcome reporting, and number of patients analyzed.
Results: Nine hundred and eighty-four publications were initially screened for inclusion after duplicates were removed. The search identified 16 publications evaluating drug combinations for the treatment of alcohol use disorder. The majority of published trials included naltrexone combined with one of the following: gabapentin, ondansetron, acamprosate, gamma-hydroxybutyrate, sertraline, quetiapine, or escitalopram plus gamma-hydroxybutyrate. Other combinations included 5-hydroxytryptophan with carbidopa/levodopa, gamma-hydroxybutyrate with disulfiram, acamprosate with disulfiram, and mirtazapine with quetiapine. Interpretation of results across studies was limited by low statistical power, and heterogeneity of drug combinations and outcome measures. Drug combination effect sizes were comparable to those observed in single-agent trials.
Conclusions: No significant benefit for the use of combinations over single agents was observed. However, benefit may be observed when combined pharmacological interventions address specific symptoms of alcohol use disorder known to be influenced by combination components, or when combinations are used in specific subpopulations in which combination components demonstrate benefit.