Most people will experience depressed mood at some point during their lifetime, but Major Depressive Disorder (MDD) is different. MDD is the chronic, pervasive feeling of utter unhappiness and suffering, which impairs daily functioning. This disorder affects 6.7% of Americans and 350 million people worldwide. Symptoms of depression include: diminished pleasure in activities, weight changes, insomnia or hypersomnia, psychomotor agitation, fatigue, feelings of worthlessness and guilt, poor concentration, and suicidality.
Approximately one-third of patients fail to achieve remission of depressive symptoms when using current, FDA-approved medications. Additionally, after two failed trials, the likelihood of treatment success drops to 15% or less. If an individual fails two or more adequate antidepressant trials, he or she is classified as treatment-resistant.