Pharmacodynamic and pharmacokinetic comparison of two formulations of lorazepam and placebo

摘要

AbstractNine healthy male volunteers took part in a comparison of the pharmacokinetic profiles and effects on psychomotor performance and memory following single dosing with an experimental sustained release (SR) and a conventional release (CR) formulation of lorazepam. There was evidence of a sustained release profile for the SR formulation which had a latertmax(median 8 h) and significantly lower peak serum concentration (mean 12·1 ng ml−1) compared with CR lorazepam (2 h and 21.8 ng ml−1respectively). The effect of SR lorazepam on pharmacodynamic variables occurred later and was less intense than with CR lorazepam. Good correlations were obtained between most of the pharmacodynamic parameters measured and the logarithm of the serum concentration for both formulations, with the exception of the choice reaction time test for SR lorazepam. However, both formulations produced a similar degree of impairment of 24h re