OBJECTIVE: Case report of a pharmacokinetic interaction between diltiazem and nortriptyline. METHODS: Determination of plasma nortriptyline concentrations by HPLC. Calculation of nortriptyline clearances and half-life by formulae used routinely in therapeutic drug monitoring. RESULTS: The average plasma concentration of nortriptyline at steady state (Css) divided by the amount of nortriptyline administered per time rose significantly in a patient with concomitant administration of diltiazem, suggesting increased bioavailability and/or decreased clearance of nortriptyline. CONCLUSIONS: There is a significant pharmacokinetic interaction between diltiazem and nortriptyline, which is probably due to a reduction in the first pass clearance of nortriptyline, leading to an increase in its bioavailability.
OBJECTIVE: Case report of a pharmacokinetic interaction between diltiazem and nortriptyline. METHODS: Determination of plasma nortriptyline concentrations by HPLC. Calculation of nortriptyline clearances and half-life by formulae used routinely in therapeutic drug monitoring. RESULTS: The average plasma concentration of nortriptyline at steady state (Css) divided by the amount of nortriptyline administered per time rose significantly in a patient with concomitant administration of diltiazem, suggesting increased bioavailability and/or decreased clearance of nortriptyline. CONCLUSIONS: There is a significant pharmacokinetic interaction between diltiazem and nortriptyline, which is probably due to a reduction in the first pass clearance of nortriptyline, leading to an increase in its bioavailability.
Authors: D J Hermann; T F Krol; G E Dukes; E K Hussey; M Danis; Y H Han; J R Powell; L J Hak Journal: J Clin Pharmacol Date: 1992-02 Impact factor: 3.126
Authors: L Pichard; G Gillet; I Fabre; I Dalet-Beluche; C Bonfils; J P Thenot; P Maurel Journal: Drug Metab Dispos Date: 1990 Sep-Oct Impact factor: 3.922