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European Journal of Clinical Pharmacology

, Volume 35, Issue 4, pp 385–389 | Cite as

Bioavailability and pharmacokinetics of oxazepam

  • J. Sonne
  • S. Loft
  • M. Døssing
  • A. Vollmer-Larsen
  • K. L. Olesen
  • M. Victor
  • F. Andreasen
  • P. B. Andreasen
Originals

Summary

Six healthy volunteers received oxazepam 15 mg i.v. and orally at an interval of at least one week. The kinetic variables of i.v. oxazepam were: elimination half-life (t1/2β) 6.7 h, total clearance (CL) 1.07 ml·min−1·kg−1, volume of distribution (Vc) 0.27 l·kg−1 (0.21–0.49) and volume of distribution at steady-state (Vss) 0.59 l·kg−1. The intravenous disposition of unbound oxazepam was characterized by a clearance of 22.5ml·min−1·kg−1 and a distribution volume of 12.3 l·kg−1. After oral oxazepam the peak plasma level was reached in 1.7 to 2.8 h. The plasma t1/2β at 5.8 h was not significantly different from the i.v. value. Absorption was almost complete, with a bioavailability of 92.8%. Urinary recovery was 80.0 and 71.4% of the dose after intravenous and oral administration, respectively. Renal clearance (CLR) of the glucuronide metabolite was 1.10 ml·min−1·kg−1 (0.98–1.52). Oxazepam was extensively bound to plasma protein with a free fraction of 4.5%.

Key words

oxazepam pharmacokinetics i.v.-/oral administration bioavailability healthy volunteers 

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Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • J. Sonne
    • 1
    • 4
  • S. Loft
    • 2
  • M. Døssing
    • 1
  • A. Vollmer-Larsen
    • 1
  • K. L. Olesen
    • 1
  • M. Victor
    • 1
    • 2
    • 3
  • F. Andreasen
    • 3
  • P. B. Andreasen
    • 1
  1. 1.Medical Department FGentofte University HospitalGentofte, CopenhagenDenmark
  2. 2.Department of PharmacologyUniversity of CopenhagenDenmark
  3. 3.Institute of PharmacologyUniversity of AarhusAarhusDenmark
  4. 4.Medical Department CHerlev Hospital Herlev RingvejHerlevDenmark

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