 - Have failed more than 3 adequate antidepressant trials during the current MDE. Some examples of adequate dosage of an antidepressant trial include either 150 mg of imipramine or its tricyclic equivalent, 60 mg of phenelzine or its monoamine oxidase inhibitor equivalent, 20 mg of fluoxetine or its SSRI-equivalent, 150mg of bupropion, 300mg of trazodone or nefazodone, 75 mg of venlafaxine, 60mg of duloxetine, or 15mg of mirtazapine. A trial of adequate duration was defined as one during which the patient was on any given antidepressant at an adequate dose for a minimum of 6 weeks. 