Determination of the Antidepressant Duloxetine in Plasma to Improve the Knowledge of the Analgesic Action of Antidepressants on Chronic Neuropathic Pain

University Hospital, Strasbourg, France8 enrolled

Overview

The primary purpose of this protocol is to evaluate the lowest plasma concentration (ie before the daily taking dose of duloxetine) in patients relieved of at least 30% of their neuropathic pain with duloxetine treatment. The secondary purpose of this protocol is to determine plasmatic concentration peak (ie 6 hours after taking duloxetine) in patients relieved of at least 30% of their neuropathic pain with duloxetine treatment. Others secondary purposes are to evaluate the intensity of neuropathic pain, to assess the degree of pain relief and to evaluate the sensation of the global improvement experienced by the patient.

Study Type

INTERVENTIONAL

Allocation

Purpose

OTHER

Masking

NONE

Enrollment

Conditions

Neuropathic Pain

Interventions

Eligibility

Sex: ALLMin age: 40 YearsMax age: 75 Years

Medical Language ↔ Plain English

Inclusion criteria: * aged 40 to 75 years old * relieved of their neuropathic pain by 60 mg of duloxetine treatment (with a differential of\> 30% in the intensity of neuropathic pain with NRS, before and after treatment initiation) Exclusion criteria: * concomitant treatment with enoxacin, fluvoxamine, flecainide, propafenone, metoprolol, risperidone, verapamil, omeprazole, modafinil, mequitazine, propafenone, tamoxifen, Monoamine Oxidase Inhibitors.

Outcomes

Primary Outcomes

Measurement of the lowest plasma concentration of duloxetine in pmol/mL.

Time frame: The concentration of duloxetine is measured by liquid chromatography coupled to tandem mass spectrometry on blood sample taken at the inclusion visit (V0), before the daily morning dose of duloxetine.

Secondary Outcomes

Measurement of the plasma concentration peak of duloxetine in pmol/mL.

Time frame: The concentration of duloxetine is measured by liquid chromatography coupled to tandem mass spectrometry on blood sample taken during the V1 visit (28 days after V0, 6 hours after the daily morning dose of duloxetine).