Sequential Tranylcypromine (TC), TC + Dextroamphetamine and TC + Triiodothyronine for Refractory Depression

Inclusion Criteria: * Ages between 18-65 * Major Depression * At least two prior ineffective antidepressant trials (at least 2 different mechanisms) or 1 inadequate ECT trial (at least 8 bilateral treatments) * Physically healthy Exclusion Criteria: * Known Tranylcypromine allergy * Unable to follow tyramine-free diet * Known allergy, intolerance or prior addiction to any stimulant would preclude patient's inclusion in the Dextroamphetamine portion of the protocol * Current substance use disorder including alcohol)(past six months); ever dependent on stimulants would preclude Dextroamphetamine portion of the protocol * Unable or unwilling to discontinue antidepressants including OTC antidepressants such as St. John's Wort * History of psychosis, such as schizophrenia or psychotic depression; history of bipolar mania will be allowed if on adequate mood stabilizer * Suicidal ideation/activity that makes outpatient treatment unsafe, unless protocol can be conducted as inpatient * Current systolic BP \> 149 or diastolic BP \> 89 mm Hg (two readings); adequately treated hypertension is acceptable * Evidence of hypo- or hyperthyroidism * Pregnancy, lactation, refusal to use adequate birth control