The effects of the Chinese herbal medicine EMF01 on salicylate-induced tinnitus in rats

Aim of the study: Traditional Chinese medicine (TCM) has been reported to successfully alleviate tinnitus, although well-controlled studies have not been conducted. In this study, we attempted to test a TCM, Er Ming Fang (EMF01) containing Rehmannia glutinosa, Cornus officinalis, Salvia mittiorrhiza, Pueraria, Schisandra chinensis, Poria cocos and Platycodon grandiflorum, on salicylate-induced tinnitus in rats, using a conditioned lick suppression paradigm. Materials and methods: A pilot study examined the effect of 8.75 g/kg and 17.5 g/kg EMF01 (delivered by oral gavage for 20 days) and showed a slight decrease in the suppression ratio (SR) in the 8.75 g/kg group. In order to confirm the possible effect of EMF01 on tinnitus at 8.75 g/kg, a further study was carried out with a larger sample size. Results: While there were statistically significant differences between the treatment groups, post hoc tests revealed that EMF01 did not have any significant effect on salicylate-induced tinnitus. Conclusions: While this study does not support the efficacy of EMF01 in the treatment of salicylate-induced tinnitus, further studies should be conducted to determine if it alleviates tinnitus associated with acoustic trauma.