CONCLUSION Otolith function is significantly affected by alcohol ingestion and the higher the dosage, the greater the effect. OBJECTIVE To determine how the effect of a 5 oz (150 ml) dose of alcohol differs from an earlier study examining the effect of 3 oz (90 ml) on ocular counterrolling (OCR). SUBJECTS AND METHODS Twenty subjects underwent OCR testing before and after drinking 5 oz of 80 proof vodka. RESULTS Blood alcohol levels (BAL) of the subjects ranged from 0.09 to 0.18%. Three measures of OCR were considered. Amplitude was significantly reduced post-alcohol; disconjugacy was significantly increased post-alcohol; smoothness was not significantly different pre- and post-alcohol. In contrast, the lower 3 oz study produced BAL of 0.04-0.09% and resulted in significantly reduced OCR amplitude, no significant change in disconjugacy, but a significant improvement in smoothness. The increase in BAL produced further impairment of amplitude and conjugacy but eliminated the benefit of smoothness.