Rate of entrance of benzodiazepines into the brain determined by eye movement recording.

Abstract

1 Peak saccadic velocity of horizontal eye movements, saccade duration at 30 degrees of amplitude and saccade reaction time were measured in six drug free male subjects. 2 In two separate experiments, intravenous doses of diazepam (5 mg), lorazepam (2 mg), chlordiazepoxide (25 mg) and placebo were given, and eye movement recordings were made before and at frequent intervals after drug administration. 3 All the benzodiazepines produced a significant impairment of peak saccadic velocity and saccade duration. Only lorazepam significantly affected saccade reaction time. 4 Time to achieve maximum effect was 10 min after diazepam, 29 min after lorazepam and 42 min after chlordiazepoxide.