Duloxetine for Treatment of Painful Temporomandibular Joint Disorder

Inclusion Criteria

• Patients with chronic TMJD pain of two weeks duration
• Age 18 and older
• Confirmed craniofacial pain of nonodontogenic origin by the Research Diagnostic Criteria for temporomandibular disorders (TMD-RDC)
• Concomitant medications are permitted, except those which may convey analgesia
• Females who are neither pregnant, as verified by a urine-based pregnancy test, nor breast-feeding
• Female subjects of childbearing potential and those who are post-menopausal for less than 2 years must be using/willing to use a medically approved method of contraception (i.e., oral, transdermal or implanted contraceptive devices, intrauterine device, diaphragm, condom, abstinence, or surgical sterility during the course of the study
• Able to read and comprehend the rating scales, study instructions, and the consent form
• Pain score of 4 or greater on the baseline VAS (0-10)

Exclusion Criteria

• Undergone any type of TMJ surgery or had TMJ growth disturbances, neoplasm, or injury to the TMJ area within the past six months
• Taking analgesic or anti-inflammatory drugs, steroids, antidepressants, antiepileptics, or opioid medications that may confound the assessment of analgesia
• Subjects with primary psychiatric diagnosis of major depression, suicidal ideation, or history of suicide attempt as assessed by medical history and the Mini International Neuropsychiatric Interview (MINI) are not eligible. Subjects with a score above average or higher in comparison with normative scores on the Beck Depression Inventory (BDI) will be allowed to participate
• Exclusions based on the effects of duloxetine:
• Known hypersensitivity to duloxetine or its inactive ingredients
• Subjects with: renal impairment or end stage renal disease; urinary retention or hesitation, delayed gastric emptying; substantial alcohol use or evidence of chronic liver disease, hepatic insufficiency and hepatotoxicity; bleeding disorders, orthostatic hypotension, uncontrolled high blood pressure; recent history of myocardial infarction or unstable coronary artery disease; seizure disorder, history of bipolar disorder or mania, general anxiety disorder (GAD); hyponatremia; uncontrolled narrow-angle glaucoma.
• Treatment with an monoamine oxidase inhibitor (MAOI) within 30 days of randomization, or potential need to use an MAOI during the study or within 5 days of discontinuation of the drug
• Concomitant use of medications such as: NSAIDs, warfarin, aspirin or other drugs that affect coagulation; Thioridazine and inhibitors of CYP1A2 which affect metabolism of duloxetine; serotonergic drugs like triptans and MAOIs which increase the risk of Serotonin Syndrome; drugs that affect gastric acidity
• Contraindications to acetaminophen use
• Ever been treated with duloxetine