Wala E P, Martin W R, Sloan J W
Department of Anesthesiology, University of Kentucky, Lexington 40536-0216.
Pharmacol Biochem Behav. 1993 Apr;44(4):857-64. doi: 10.1016/0091-3057(93)90017-n.
Previous studies suggested that the extensive accumulation of benzodiazepines is an important factor in the induction of physical dependence. The mechanistic basis for accumulation of nordiazepam (ND) and its metabolite, oxazepam (OX), have been examined in crossover studies in drug-naive and in ND-dependent dogs that exhibited a flumazenil-precipitated abstinence syndrome. ND and parent OX have similar pharmacokinetic profiles. Steady-state plasma levels of ND and OX cannot be predicted from single-dose pharmacokinetics. Reduced plasma clearance of ND and altered plasma protein binding were observed in dogs physically dependent upon ND. The benzodiazepine antagonist, flumazenil, significantly reduces steady-state plasma levels of total and free ND.
