The pharmacokinetics of alcohol for essential tremor

Objective: We investigated the time course of the effect of alcohol on tremor characteristics in 10 patients with essential tremor (ET).

Methods: The dosage of alcohol was adapted for each individual according to weight and sex to receive a target response of ˜0.8‰ blood alcohol level. The postural tremor amplitude at the wrist was recorded using an accelerometer placed on the dorsum of the hand. Tremor recordings, a modified Fahn-scale, the visual analogue-scale (VAS), Archimedes spirals and blood alcohol were measured at baseline and at 10, 20, 30, 40, 50, 60, 90 minutes, in the evening and the next morning after alcohol ingestion.

Results: The time course of the anti-tremor-effect showed a strong improvement up to 50–60% of tremor intensity, modified Fahn-score and Archimedes spirals from 10 to 90 minutes. This course of improvement showed a small recurrence of all tremor parameters at the top of blood alcohol 30 minutes after alcohol ingestion. A severe deterioration of tremor characteristics occurs after >3 hours.

Conclusion: We conclude that alcohol is a very effective drug in therapy of essential tremor. The effect is only short and exhibits a severe rebound after >3 hours and the next morning. The reason for the biphasic course with the reproducible recurrence of tremor after 30 minutes is unclear and has to be investigated in further studies. Based on these findings we will develop a diagnostic tool which facilitates the diagnosis of essential tremor.