[Treatment of tinnitus with intravenous lidocaine]

Intravenous lidocaine was administered in 155 cases (196 ears) with tinnitus. The injection of lidocaine, at a dose of 60 mg in men and 40 mg in women was repeated five times. The intensity of tinnitus was evaluated along a scale ranging from 0 to 10, indicating the level prior to injection. A scale ranging from 0 to 7 was estimated to be effective. After evaluation of the drug by using a double-blind test, indications for therapy were analyzed statistically according to clinical characteristics. The results obtained were as follows: 1) The effect was confirmed by using a double-blind test. 2) The effective rate was 60.2%. 3) Older cases, especially with presbyacusis, had the best indications for therapy. 4) From the clinical viewpoint of the characteristics of tinnitus, cases with hearing levels above 40dB or with dull onomatopoeic sounds were considered to have better indications for therapy. 5) None of the side effects experienced were severe, and all were transient.