Effectiveness of acamprosate for tinnitus: a systematic review and meta-analysis of clinical trials

ABSTRACT Introduction The effectiveness of tinnitus treatment represents a huge gap in the medical science. Acamprosate is a glutamatergic antagonist drug and GABA-agonist that could be used to control tinnitus due to its action on peripheral and central neurotransmission. Purpose To assess the effectiveness of acamprosate in the treatment of tinnitus. Material and Methods This is a systematic review and we searched for randomized clinical trials linking acamprosate to tinnitus in six databases: Cochrane - Central Register of Controlled Trials - CENTRAL (2021), PUBMED (1966-2021), EMBASE (1974-2021), IBECS (1982-2021), QINSIGHT (2021) and SCOPUS (2021). Two researchers independently extracted the data and assessed the quality of the studies. Results Two trials involving 121 patients were included. The methodological quality of these studies was low. Both studies evaluated as primary outcome the efficacy of acamprosate in improving tinnitus. The meta-analysis by random model resulted in no significant difference between the groups treated with acamprosate and placebo (RR = 3,69, 95% CI 0,87-15,62; p=0,08), considering tinnitus improvement. Conclusions: There is no evidence that acamprosate is effective for tinnitus treatment. We recommend new trials using rigorous methodology. Randomization and blinding should be of the highest quality, given the subjective nature of tinnitus and the strong likelihood of a placebo response. The CONSORT statement should be used in the design and reporting of future studies.