Ginkgo biloba extract for the treatment of tinnitus.

Previous studies have shown contradictory results of Ginkgo biloba extract (GBE) treatment of tinnitus. The present study was divided into two parts: first an open part, without placebo control (n = 80), followed by a double-blind placebo-controlled study (n = 20). The patients included in the open study were patients who had been referred to the Department of Audiology, Sahlgren's Hospital, Göteborg, Sweden, due to persistent severe tinnitus. Patients reporting a positive effect on tinnitus in the open study were included in the double-blind placebo-controlled study (20 out of 21 patients participated). 7 patients preferred GBE to placebo, 7 placebo to GBE and 6 patients had no preference. Statistical group analysis gives no support to the hypothesis that GBE has any effect on tinnitus, although it is possible that GBE has an effect on some patients due to several reasons, e.g. the diverse etiology of tinnitus. Since there is no objective method to measure the symptom, the search for an effective drug can only be made on an individual basis.