Summary
We have studied the pharmacokinetics and absolute systemic availability of indoramin (50 mg) given orally in solution or as a tablet with reference to intravenously administered drug (0.15 mg/kg) in 9 healthy volunteers.
After intravenous administration the median apparent volume of distribution was 6.3l·kg−1, plasma clearance was 20.0 ml·min−1·kg−1, and terminal half-time was 4.1 h.
When given by tablet indoramin was absorbed with moderate rapidity, with a median tmax of 1.5 h. The median systemic availability was 24%.
After oral administration in solution the drug was more rapidly absorbed, with a median tmax of 1.0 h (p<0.01). The median systemic availability was 43% (15–85%).
Plasma concentrations of an active metabolite, 6-hydroxyindoramin, after single oral doses in either dosage form, were of a similar order to those of unchanged drug and fell with similar rapidity. After intravenous administration, however, concentrations of the metabolite were negligible.
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Pierce, D.M., Abrams, S.M.L. & Franklin, R.A. Pharmacokinetics and systemic availability of the antihypertensive agent indoramin and its metabolite 6-hydroxyindoramin in healthy subjects. Eur J Clin Pharmacol 32, 619–623 (1987). https://doi.org/10.1007/BF02455999
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DOI: https://doi.org/10.1007/BF02455999