Purpose: The main aim of this study was to assess the effect of gabapentin on tinnitus via a systematic review.
Method: An electronic search of literature as well as a hand search were conducted. Only double-blind randomized controlled trials (RCTs) that met all of the inclusion criteria were included in this review. The Cochrane Collaboration tool for risk of bias assessment was used to investigate the validity of the included studies. Meta-analysis was not appropriate due to inadequate details in reporting the data in the included studies. Hence, qualitative synthesis and interpretation of the data were carried out.
Results: Two studies that met the inclusion criteria were included in the review. Fourteen studies were excluded. There were substantive within-study clinical heterogeneities with regard to the baseline tinnitus handicap scores, duration of tinnitus, and severity of hearing loss in the included double-blind RCTs.
Conclusion: The authors of both studies reported that gabapentin was not superior to placebo in their primary outcomes. However, following the assessment of risk of bias and within-study clinical heterogeneities, this review concludes that there is insufficient evidence regarding the effect of gabapentin on tinnitus.