This is a three-armed clinical trial examining the effect of 5-hydroxytryptophan and creatine
monohydrate as augmenting agents for the treatment of depression. Subjects will be randomized
between 5-HTP + placebo, creatine + placebo, and 5-HTP + creatine, for 8 weeks. The ability
of the interventions to affect biomarkers associated with depression will be assessed using
brain phosophorus magnetic resonance spectroscopy, functional connectivity imaging, and
plasma serotonin levels.