Effects of timolol and atenolol on benign essential tremor: placebo-controlled studies based on quantitative tremor recording.

Two different beta-adrenoreceptor antagonists, atenolol and timolol, were separately compared with a placebo in the suppression of essential tremor. In two-week single-blind placebo-controlled studies with cross-over, timolol (5 mg twice daily) and atenolol (100 mg once daily) produced an equal reduction in sitting heart rate and sitting blood pressure. Timolol was effective in reducing tremor while atenolol failed to reduce tremor amplitude. These results indicate that essential tremor can be reduced but not blocked, by the adrenergic blocker timolol with both beta 1 and beta 2 blocking properties; but not by the relatively selective beta 1 blocking drug atenolol. Possibly, the tremor reduction is medicated by a peripheral effect on beta 2 adrenoreceptors.