Clinical Pharmacokinetics

, Volume 16, Issue 6, pp 387–391 | Cite as

Single-Dose and Steady-State Pharmacokinetics of Doxazosin Given in Combination with Chlorothiazide to Hypertensive Subjects

  • E. L. Conway
  • J. J. McNeil
  • L. Meng
  • O. H. Drummer
  • L. G. Howes
  • K. Raymond
  • W. J. Louis
Original Research Article

Summary

The pharmacokinetics of doxazosin were determined in hypertensive subjects after a single dose of 1mg, and at steady-state while receiving doses of 1, 2, 4 and 8mg of the drug daily. Chlorothiazide 500mg once daily was administered as additional therapy throughout the study. After a single dose doxazosin was rapidly absorbed, with peak plasma drug concentrations (Cmax) occurring after 2.1 ± 0.4 hours. The elimination half-life in plasma was 10.7 ± 1.2 hours. These parameters remained essentially unchanged during maintenance administration of doxazosin at each of the dose levels. Calculations of Cmax and area under the concentration-time curve (A UC0→∞) indicated that the pharmacokinetic disposition of the drug remained linear over the dose range 1 to 8mg.

Keywords

Clinical Pharmacology Prazosin Doxazosin Hypertensive Subject Terazosin 

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Copyright information

© ADIS Press Limited 1989

Authors and Affiliations

  • E. L. Conway
    • 1
  • J. J. McNeil
    • 1
  • L. Meng
    • 1
  • O. H. Drummer
    • 1
  • L. G. Howes
    • 1
  • K. Raymond
    • 1
  • W. J. Louis
    • 1
  1. 1.Clinical Pharmacology and Therapeutics Units, Austin HospitalUniversity of MelbourneHeidelbergAustralia

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