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Effect of Duloxetine and Venlafaxine on the Pharmacokinetics and Pharmacodynamics of Oral Tramadol: A Three-phase Randomized Balanced Cross-over Study in Healthy Volunteers

This study has been completed.
Information provided by (Responsible Party):
Turku University Hospital Identifier:
First received: September 28, 2011
Last updated: May 21, 2012
Last verified: May 2012
Tramadol is an opioid analgesic, which is widely used in the treatment of acute and neuropathic pain. After oral administration, tramadol is rapidly and almost completely absorbed. Tramadol is extensively metabolised by O- and N-demethylation, which are catalysed by the liver CYP-450 enzymes. O-desmethyltramadol is an active metabolite and its formation is catalysed by CYP2D6. This study is aimed to investigate the possible interaction of oral tramadol with duloxetine and venlafaxine. Duloxetine is known to inhibit CYP2D6. Twelve healthy male or female adult non-smoking volunteers aged 18-40 years with body weights within ±15% of the ideal weight for height are taken into the study. Primary endpoints of the study are plasma concentrations of tramadol and its metabolites.

Condition Intervention Phase
Healthy Drug: Placebo Drug: Duloxetine Drug: Venlafaxine Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single (Participant)
Primary Purpose: Basic Science

Resource links provided by NLM:

Further study details as provided by Turku University Hospital:

Primary Outcome Measures:
  • Concentration of tramadol and its metabolites in plasma [ Time Frame: 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8, 10, 12, 24, 48 hours after administration of tramadol ]

Secondary Outcome Measures:
  • Serotonin concentrations [ Time Frame: 0, 4 and 8 hours after tramadol administration ]
    Serotonin concentrations will be analyzed with chromatographical methods from the blood samples drawn 0, 4 and 8 hours after tramadol administration

  • Pharmacodynamic effects [ Time Frame: 1, 2, 3, 4, 5, 6, 8, 10, 12 hours after administration of tramadol ]
    The psychomotor effects of tramadol will be assessed with the measurement of pupil size with Cogan's pupillometer, Maddox wing test and digit symbol substitution test

  • Analgesia [ Time Frame: 1, 2, 3, 4, 5, 6, 8, 10, 12 hours after the administration of tramadol ]
    The analgesic effect of tramadol will be evaluated using the cold pressor test. Briefly, the subject's hand is immersed into ice-cold water of + 4° C up to the wrist. The subject is told to keep his or her hand in the water and to report when the cold sensation becomes painful. Cold pain threshold is defined as the latency from the immersion of the hand to the subject's first report of pain. Cold pain intensity is assessed at 30 s intervals following immersion of the hand in cold water for up to 60s . A verbal numerical rating scale of 0-100 will be used.

Enrollment: 12
Study Start Date: October 2011
Study Completion Date: January 2012
Primary Completion Date: January 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Placebo Drug: Placebo
The subjects will be given orally placebo twice a day for 8 days prior to the study.
Active Comparator: Duloxetine Drug: Duloxetine
The subjects will be given orally duloxetine 30mg twice a day for 8 days prior to the study.
Active Comparator: Venlafaxine Drug: Venlafaxine
The subjects will be given orally venlafaxine 37,5mg twice a day for 8 days prior to the study.


Ages Eligible for Study:   18 Years to 40 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Healthy volunteers
  • Age 18-40
  • Body weight within ±15% of the ideal weight for height

Exclusion Criteria:

  • A previous history of intolerance to the study drugs or to related compounds and additives
  • Concomitant drug therapy of any kind for at least 14 days prior to the study
  • Existing or recent significant disease
  • History of hematological, endocrine, metabolic or gastrointestinal disease, including gut motility disorders
  • History of asthma or any kind of drug allergy
  • Previous or present alcoholism, drug abuse, psychological or other emotional problems that are likely to invalidate informed consent, or limit the ability of the subject to comply with the protocol requirements
  • A positive test result for urine toxicology
  • A "yes" answer to any one of the Abuse Questions
  • Pregnancy or nursing
  • Donation of blood for 4 weeks prior and during the study
  • Special diet or life style conditions which would compromise the conditions of the study or interpretation of the results
  • Participation in any other studies involving investigational or marketed drug products concomitantly or within one month prior to the entry into this study
  • Smoking for one month before the start of the study and during the whole study period
  • Any history of coagulation abnormality, also in first degree relatives
  Contacts and Locations
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Please refer to this study by its identifier: NCT01443520

Department of Anaesthesiology, Intensive Care, Emergency Care and Pain Medicine, Turku University and Turku University Hospital
Turku, Finland
Sponsors and Collaborators
Turku University Hospital
  More Information

Responsible Party: Turku University Hospital Identifier: NCT01443520     History of Changes
Other Study ID Numbers: 97/180/2011
2011-003259-20 ( EudraCT Number )
Study First Received: September 28, 2011
Last Updated: May 21, 2012

Keywords provided by Turku University Hospital:

Additional relevant MeSH terms:
Duloxetine Hydrochloride
Venlafaxine Hydrochloride
Serotonin and Noradrenaline Reuptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Physiological Effects of Drugs
Sensory System Agents
Peripheral Nervous System Agents
Antidepressive Agents
Psychotropic Drugs
Dopamine Agents
Antidepressive Agents, Second-Generation processed this record on August 22, 2017