International Journal of Legal Medicine

, Volume 121, Issue 3, pp 169–174 | Cite as

Medicolegal aspects of tetrazepam metabolism

  • Marion Pavlic
  • Kathrin Libiseller
  • Petra Grubwieser
  • Heinrich Schubert
  • Walter Rabl
Original Article


The benzodiazepine tetrazepam is primarily muscle relaxant with comparably lower central sedating effects and is therefore commonly prescribed for muscle spasms of different origins. To evaluate tetrazepam metabolism, a study was conducted with ten healthy volunteers. Blood and urine samples were regularly collected after the intake of 50 mg tetrazepam. Toxicological analyses revealed that tetrazepam is also metabolized to diazepam and further to nordazepam, which has not yet been reported. Tetrazepam and diazepam could be detected in urine samples at least 72 h after intake, the diazepam concentration being 33% (±14% SD), on average, of the tetrazepam concentration. On the basis of three case histories, the importance of the detection of these newly described metabolites is shown as necessary to prevent false accusations and potential negative legal consequences for examined persons.


Tetrazepam Diazepam Nordazepam Forensic toxicology 



The authors would like to thank Dr. Herbert Oberacher for valuable discussions and Mrs. Elisabeth Unterdorfer and Mr. Karl-Heinz Pramstrahler for their technical support within the laboratory.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Marion Pavlic
    • 1
  • Kathrin Libiseller
    • 1
  • Petra Grubwieser
    • 1
  • Heinrich Schubert
    • 2
  • Walter Rabl
    • 1
  1. 1.Institute of Legal MedicineInnsbruck Medical UniversityInnsbruckAustria
  2. 2.Department of Plastic and Reconstructive SurgeryInnsbruck Medical UniversityInnsbruckAustria

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