Summary
Intra- and inter-subject variation in the kinetics of indoramin and its active metabolite 6-hydroxyindoramin have been studied in 5 young, healthy, male volunteers administered a single oral dose of the drug on 5 separate occasions.
Inter-subject variation represented the main source of variability in indoramin plasma concentrations with, for example, the between-subjects sum of squares (a measure of the contribution to the total variability) representing around 97% of the total sum of squares for Cmax and AUC (0–24). Intra-subject and inter-subject coefficients of variation (C.V.s) were circa 20% and 100% respectively for both these parameters.
Variability in 6-hydroxyindoramin concentrations was much lower and was approximately equally derived from intra- and inter-subject variation, with the C.V.s being approximately 44% for both Cmax and AUC (0–24).
The results imply that the kinetic behaviour of indoramin within an individual will prove relatively consistent, despite widespread inter-subject variation, once an appropriate dosage regime has been established.
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Pierce, D.M., Abrams, S.M.L. & Franklin, R.A. Intra- and inter-subject variation in the pharmacokinetics of indoramin and its 6-hydroxylated metabolite. Eur J Clin Pharmacol 35, 195–198 (1988). https://doi.org/10.1007/BF00609252
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DOI: https://doi.org/10.1007/BF00609252