Multiple-dose quazepam kinetics.

M Chung; J M Hilbert; R P Gural; E Radwanski; S Symchowicz; N Zampaglione

doi:10.1038/clpt.1984.70

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PubMed · 6705450

Multiple-dose quazepam kinetics.

M Chung·J M Hilbert·R P Gural·E Radwanski·S Symchowicz·N Zampaglione

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Abstract

Quazepam, a benzodiazepine hypnotic, was studied in normal subjects to evaluate steady-state kinetics of quazepam and of its major active plasma metabolites, 2-oxoquazepam and N-desalkyl-2-oxoquazepam, after 15 mg once daily by mouth for 14 days. The kinetics of quazepam and 2-oxoquazepam can be best described by a two-compartment open model with first-order absorption/formation kinetics. Quazepam was rapidly absorbed and its two major plasma metabolites appeared very quickly in systemic circulation. The elimination t 1/2s of quazepam, 2-oxoquazepam, and N-desalkyl-2-oxoquazepam were 41, 43, and 75 hr. Steady-state levels were predictable from the kinetic data and were reached by the seventh dose for quazepam and 2-oxoquazepam and by the thirteenth dose for N-desalkyl-2-oxoquazepam. These kinetic profiles may explain the clinical hypnotic effect of quazepam--rapid induction of sleep and long duration of clinical action without appreciable rebound insomnia.

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M Chung, J M Hilbert, R P Gural, E Radwanski, S Symchowicz, N Zampaglione. 1984. Multiple-dose quazepam kinetics.. https://doi.org/10.1038/clpt.1984.70

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