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Drug Investigation

, Volume 6, Issue 2, pp 62–69 | Cite as

Single and Multiple Dose Pharmacokinetics of a Sustained-Release Formulation of Bunazosin (E1015) in Healthy Young and Elderly Volunteers

  • Nobumichi Morishita
  • Yoshiro Tomono
  • Jiro Hasegawap
  • Paul Branagan
  • A. C. Houston
  • Werner Weber
  • Horst-Jürgen Heuer
  • Günther Pabst
Original Research Article
  • 3 Downloads

Summary

The results of 1 multiple dose and 2 single dose pharmacokinetic studies of sustained-release bunazosin (Bunazosin Retard®) 6mg in healthy elderly (n = 47) and healthy young (n = 12) volunteers are suggestive of an age-related difference in the drug’s disposition. Area under the concentration-time curve (AUC) and peak plasma concentration (Cmax) values were significantly higher [AUC: x 1.9 (male) and x 1.9 (female); Cmax x 2.0 (male) and x 1.9 (female)] in the elderly than in their younger counterparts. This difference in AUC0-48h and Cmax values appeared to be due to reduced bunazosin clearance in the elderly. Steady-state plasma bunazosin concentrations in elderly volunteers (n = 12) were achieved 9 days after initiating multiple oral dose administration of Bunazosin Retard® 6mg once daily. There was no evidence of further bunazosin accumulation after 8 days of oral dose administration.

Bunazosin Retard® 6 mg/day caused moderate to marked reductions in supine and standing systolic and diastolic blood pressures (≈ 18/15mm Hg and 32/15mm Hg, respectively, at 6 to 8 hours postdose) and a modest increase in standing heart rate (≈ 15 beats/min). This hypotensive effect was more pronounced in the elderly.

Keywords

Drug Invest Elderly Volunteer Sparteine High Performance Liquid Chro Mephenytoin 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Adis International Limited 1993

Authors and Affiliations

  • Nobumichi Morishita
    • 1
  • Yoshiro Tomono
    • 2
  • Jiro Hasegawap
    • 2
  • Paul Branagan
    • 3
  • A. C. Houston
    • 4
  • Werner Weber
    • 5
  • Horst-Jürgen Heuer
    • 5
  • Günther Pabst
    • 5
  1. 1.Center for Clinical Pharmacology and BiostatisticsEisai Co., LtdBunkyo-ku, TokyoJapan
  2. 2.Section of Clinical Pharmacology, Center for Clinical Pharmacology and BiostatisticsEisai Co., LtdTokyoJapan
  3. 3.Eisai Europe Ltd, Trafalgar HouseHammersmith International CentreLondonEngland
  4. 4.Hazelton Medical Research Unit, Hazelton UKHarrogateEngland
  5. 5.LAB GmbH & Co.Neu-UlmGermany

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