, Volume 121, Issue 2, pp 242–249 | Cite as

Reversal of triazolam- and zolpidem-induced memory impairment by flumazenil

  • N. J. Wesensten
  • T. J. Balkin
  • H. Q. Davis
  • G. L. Belenky
Original Investigation


The effects of flumazenil, a benzodiazepine receptor antagonist, on triazolam- and zolpidem-induced memory impairment were investigated. Sixty subjects received oral triazolam 0.5 mg, zolpidem 20.0 mg, or placebo at 10 a.m. (n=20 per drug). Ninety minutes later, half of the subjects (n=10) in each oral drug group were administered flumazenil 1.0 mg, while the remaining half received placebo (normal saline), through indwelling venous catheters. Learning/memory tests (including Simulated Escape, Restricted Reminding, Paired-Associates, and Repeated Acquisition) were administered at that time, and at 1.5-h intervals over the next 6 h. Triazolam/placebo and zolpidem/placebo drug combinations impaired memory on all tests (allPs<0.05). However, the triazolam/flumazenil and zolpidem/flumazenil groups showed no evidence of impairment during any test session. These results demonstrate that flumazenil 1.0 mg rapidly and lastingly reverses memory impairment caused by agonists of the benzodiazepine receptor. Furthermore, nonsignificant trends suggested that performance of the placebo/flumazenil group was consistently better than that of the placebo/placebo group, denoting a possible role of endogenous benzodiazepine agonists in natural sleep/wake processes.

Key words

Flumazenil Triazolam Zolpidem Memory Benzodiazepine antagonist 


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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • N. J. Wesensten
    • 1
  • T. J. Balkin
    • 1
  • H. Q. Davis
    • 1
  • G. L. Belenky
    • 1
  1. 1.Department of Behavioral Biology, Division of NeuropsychiatryWalter Reed Army Institute of ResearchWashington DCUSA

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