, Volume 53, Issue 2, pp 105–109 | Cite as

Pharmacokinetics of N-desmethyldiazepam in healthy volunteers after single daily doses of dipotassium chlorazepate

  • Claes Post
  • Sune Lindgren
  • Åke Bertler
  • Harry Malmgren
Original Investigations


Dipotassium chlorazepate was administered to 12 healthy volunteers (8 males and 4 females), aged 22–38 years, as a single daily dose of 20 mg for 14 days. Plasma concentrations of N-desmethyldiazepam were monitored with a gas-chromatographic method during the medication period and for 5 days after withdrawal of the drug. The plasma half-life (t1/2), the elimination coefficient (Kβ), the concentration (\(\bar C_{{\text{ss}}} \)), and the apparent volume of distribution (Vβ) were calculated at steady state, and the mean values±SEM were 53±6 h, 0.0147±0.0013 h-1, 884±73 ng/ml, and 1.13±0.08 l/kg, respectively. A moderate interindividual variability was observed regarding these parametes. There was no tendency toward a biexponential elimination. A significant difference in the apparent volume of distribution was found when males and females were compared.

Key words

Benzodiazepines Dipotassium chlorazepate N-Desmethyldiazepam Pharmacokinetics 


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Copyright information

© Springer-Verlag 1977

Authors and Affiliations

  • Claes Post
    • 1
  • Sune Lindgren
    • 1
  • Åke Bertler
    • 1
  • Harry Malmgren
    • 1
  1. 1.Department of Clinical PharmacologyUniversity Hospital, University of Linköping and AB LeoHelsingborgSweden

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