http://web.kyoto-inet.or.jp/org/jibirin/95abstract/95-04/17.html

      Forty-two patients complaining of tinnitus were treated orally
with Choto-san (a Chinese medicine), Betahistine Mesilate, and Oxazolam
for one month. Overall effectiveness ratings: Twenty-four (57.1%)
patients seemed to improve in tone volume, twenty-two (52.4%) in
durability, and sixteen (38.1%) in worrying. Even in the early stage
of this experiment, twenty-six percent of the subjects seemed to have a
greater improvement in tinnitus than those treated with only one of the
medicines. It is suggested that these medicines are promising in the
treatment of tinnitus because there is a synergic effectiveness in
their combination.

BTW,  What's Choto-san ?