Study Evaluated the Effectiveness of Milnacipran to Reduce Pain Levels in Individuals With Chronic Migraine

Inclusion Criteria: * Individuals between the age of 18 and 65 * Headache fulfills ICHD-2 criteria for: chronic migraine, or probable medication overuse headache where individual headaches meet criteria for migraine * At least 15 headache days/month and at least 8 migraine or probable migraine days/month for the past 3 months, by patient report (including days of headache relieved with a triptan or related compound). * Age at onset of chronic migraine \< 60 years old Exclusion Criteria: * Pregnancy or attempting conception * Unable to read or write English * Use of Opiates \>/= 10 days per month * Subject has failed \>/= 4 adequate preventive trials of antidepressant medications due to lack of efficacy; at least one trial included another SNRI.(An adequate preventive trial defined as at least 6 weeks on therapeutic dose \[150mg of amitriptyline or nortriptyline or other tricyclic, 150mg of venlafaxine, 60mg of duloxetine\]) * Subjects on antidepressant medications, including SNRIs who cannot safely withdraw from those medications, in the assessment of the PI. Subjects on other headache preventives (beta blockers, antiepileptic drugs), at stable dose for at least three months, will be allowed to participate. A. Subjects on other headache preventives may be included in the study if the medication has been at a stable dose for 3 months. * Presence of fibromyalgia or another pain or medical disorder that would make it difficult for patient to distinguish headache-related quality of life from overall health related quality of life. * Uncontrolled or unstable psychiatric disorder (PHQ-9 score or GAD-7 score \>15 with sentinel questions \>/=4, or in opinion of examiner), or anticipated need for change in psychotropic medications during duration of study period; or suicidality. * Chronic kidney disease, liver disease, or any poorly controlled medical condition