The effect of intra-venous lidocaine and several different doses oral tocainide HCl on tinnitus. A dose-finding study.

As part of preliminary studies for an investigation to assess the place of some drugs, including tocainide HCl, in the treatment of tinnitus, the present study was performed to establish the appropriate dose for tocainide. The effect of lidocaine HCl on tinnitus was studied in a double-blind controlled cross-over study in 22 patients. Lidocaine appeared to give significant relief. To select an optimal daily dose for the lidocaine analog tocainide HCl, this drug was administered orally to 19 patients with obstructive tinnitus in seven 4-day periods. This could be done in a single-blind controlled trial. A different dose was given in each period. Comparison of the effect on tinnitus and the associated side effects led to the choice of a daily dose of 900 mg. The effect of lidocaine HCl appeared to have no prognostic value for the effect of tocainide HCl on the tinnitus in the individual patient.