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Amitriptyline: linear or nonlinear kinetics in every day practice?

S Vandel·G Bertschy·B Vandel·G Allers·R Volmat
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Abstract

The linearity of the (AMT) kinetics of amitriptyline has been tested in 135 depressed dosed twice daily by measuring plasma. Their (AMT) and nortriptyline (NT) levels under steady-state conditions. The AMT concentration/dose ratios at low and high dosages were not significantly different and there was a linear relationship between the dose ratios and the concentration ratios. No change in the metabolic ratio (AMT/NT) was observed between the two dosages. Although the results are consistent with linear AMT kinetics, there may have been nonlinear kinetics in some patients as the ratio between the concentration/dose ratios in them at low and high dosages was greater than one. Those patients were characterized by a low concentration/dose ratio at low dosage. No clinical adverse effect appeared in the study.

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BibTeXRIS

S Vandel, G Bertschy, B Vandel, G Allers, R Volmat. 1989. Amitriptyline: linear or nonlinear kinetics in every day practice?. https://doi.org/10.1007/bf00562551

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