In 1935 Barany serendipitously discovered the temporary relief of tinnitus after lignocaine injection of nasal turbinates.1 Since that time, other agents known to suppress the activity of excitable membranes have been tried, including antiarrhythmic and anti-convulsant drugs. Among such drugs, carbamazepine has the best documented efficacy in patients with a positive lignocaine test,2 but is generally unhelpful in unselected tinnitus populations and often discontinued due to adverse effects.2 3

A 53 year old man with viral cardiomyopathy developed severe (60 dB) tinnitus after bilateral temporal lobe strokes. Various treatments including masking and diazepam were unhelpful. Carbamazepine (200 mg nightly) was effective, but was withdrawn due to progressive hyponatraemia (120 mM after two weeks of therapy), followed by the rapid recurrence of tinnitus. Sodium valproate (200 mg twice daily) was also promptly effective in suppressing tinnitus, and was well tolerated until his death due to cardiac arrhythmia one month later.

In part due to its diverse aetiology, pharmacotherapy of tinnitus has met with very limited success.2 4 Uncontrolled trials in the French3 and Japanese5 literature have indicated benefit from sodium valproate in selected patients, but its use seems not to have been described in English apart from a specialist monograph.2 Tinnitus loudness5 and sensorineural pathology3 but not lignocaine response5 seem to predict response. Valproate may also differ from carbamazepine in that it seems better tolerated in an unselected tinnitus population.3 Controlled studies of valproate for this common, often debilitating4 condition seem warranted.