Optimal Dose of Baclofen for the Treatment of Alcohol Use Disorder: A Systematic Review and Dose-Response Meta-analysis.

Background and objectives: Baclofen, a traditional treatment for spasticity, is gaining interest for its use in alcohol use disorder (AUD). To assist clinicians in using baclofen for effective and safe treatment of AUD, we investigated the optimal target dosage of baclofen through a systematic review and dose-response meta-analysis.

Methods: We searched Cochrane, EMBASE, MEDLINE via PubMed, PsycINFO, ClinicalTrials.gov, and the International Clinical Trials Registry Platform for randomized controlled trials on 1 and 2 April 2024. Inclusion criteria were patients aged ≥ 18 years diagnosed with AUD according to Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV, DSM-IV-TR, or International Classification of Diseases (ICD)-10, and treated with baclofen monotherapy. Continuous outcomes-percent days abstinent, drinks per drinking day, heavy drinking days (HDDs), craving, and anxiety-were analyzed as mean or standardized mean differences. Binary outcomes-relapse and dropout, including due to adverse events-were analyzed as odds ratios. Each outcome was assessed using the Cochrane Risk of Bias 2.0 tool. A one-stage random-effects dose-response meta-analysis was performed using restricted cubic splines with fixed knots at 10%, 50%, and 90% percentiles.

Results: A total of 14 trials (1344 patients) were included. Increasing the dose of baclofen up to 50-60 mg/day was associated with a higher percent days abstinent and reduced craving. However, a higher baclofen dose increases the risk of dropout due to adverse events. Commonly observed adverse events were drowsiness, sedation, somnolence and fatigue. Baclofen up to 50-60 mg/day did not significantly affect drinks per drinking day, HDDs, anxiety, relapse or dropout. Doses > 60 mg/day lacked reliable evaluation due to limited data and study heterogeneity.

Conclusions: Baclofen up to 50-60 mg/day may increase percent days abstinent and reduce craving, but may increase dropout due to adverse events. Clinicians should carefully consider individual patient factors when prescribing baclofen to patients with AUD.