Pharmaceutisch Weekblad

, Volume 12, Issue 2, pp 71–74 | Cite as

Pharmacokinetics of baclofen in spastic patients receiving multiple oral doses

  • E. W. Wuis
  • M. J. M. Dirks
  • T. B. Vree
  • E. Van der Kleijn
Short Communications


The pharmacokinetics of racemic baclofen as determined from plasma and urine data in six spastic patients treated with individualized oral doses, 30–80 mg daily, are presented. Peak plasma concentrations were achieved 1.9 h (±0.7) after a dose. The fluctuation in the plasma concentration was great, ranging from 188 to 439%. The total body clearance averaged 175 ml·min−1 (±44), plasma protein binding 35% (±6). Baclofen was for the greater part excreted unchanged by the kidney, 65% (±16). Its apparent renal clearance equalled the creatinine clearance. The contribution of the renal clearance to the total body clearance can explain the previously described toxicity when renal impairment is present. The results agree with earlier reports on single doses in healthy subjects.


Baclofen Clearance Patients Pharmacokinetics 


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Copyright information

© Royal Dutch Association for Advancement of Pharmacy 1990

Authors and Affiliations

  • E. W. Wuis
    • 1
  • M. J. M. Dirks
    • 1
  • T. B. Vree
    • 1
  • E. Van der Kleijn
    • 1
  1. 1.Department of Clinical PharmacyUniversity Hospital Nijmegen Sint RadboudHB NijmegenThe Netherlands

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