耳鳴に対するリドカイン持続点滴療法の検討

抄録

Lidocaine is well known to be capable of releaving tinnitus. In the present study, we introduced an intravenous continuous lidocaine infusion therapy, and compared the therapeutic results of this method to those of an intravenous bolus injection of lidocaine. Twelve patients with tinnitus associated with idiopathic cochlear hearing loss, 6 patients with tinnitus caused by sudden deafness and 2 patients suffering from tinnitus without hearing loss underwent an intravenous bolus injection of lidocaine (60mg) followed by an intravenous continuous lidocaine infusion therapy (120mg over 30-60min). In 30% of the patients, tinnitus intensity was reduced by more than 50% after an intravenous bolus injection of lidocaine, while tinnitus intensity in 65% of the patients decreased more than 50% with an intravenous continuous lidocaine infusion therapy. In addition, the duration of tinnitus suppression was significantly prolonged by an intravenous continuous lidocaine infusion therapy. No noxious side effect was observed in this method. These results indicated that an intravenous continuous lidocaine infusion therapy might be useful for tinnitus management. An underlying mechanism of the effect of lidocaine on tinnitus was discussed with a review of the literature.