New Depression Treatments On the Horizon

By Jane Farrell

New research into the physiological causes of depression could eventually yield treatments beyond common antidepressants like Prozac and Zoloft.

According to the research, published in Current Psychiatry, treatments on the horizon include new medications, electrical and magnetic stimulation of the brain and long-term cognitive behavioral therapy for stress management.

Authors are Murali Rao, MD, and Julie M. Alderson, DO. Rao is professor and chair of the Department of Psychiatry and Behavioral Neurosciences at Loyola University Chicago Stritch School of Medicine, and Alderson is a resident at East Liverpool City Hospital in East Liverpool, Ohio.

For more than 50 years, depression has been understood as a deficiency of chemical messengers, called neurotransmitters, that carry signals between brain cells. Commonly used antidepressants are designed to either increase the release or block the degradation of three neurotransmitters – dopamine, norepinephrine and serotonin.

However, although this process has been well understood, drugs such as Zoloft, Paxil and Prozac have led to remission of depression in fewer than half of all patients

This has prompted researchers “to look beyond neurotransmitters for an understanding of depressive disorders,” Rao and Alderson write.

New theories of depression are focusing on differences in neuron density in various regions of the brain; on the effect of stress on the birth and death of brain cells; on the alteration of feedback pathways in the brain and on the role of inflammation evoked by the stress response.

Long-term stress harms cells in the brains and body, researchers have found. Chronic stress, previous research has indicated, is the leading cause of depression.

Depression treatments currently offered or on the horizon include: corticotropin-releasing hormone antagonists; dexamethasone; partial adrenalectomy; long-term cognitive behavioral therapy; ketamine and other NMDA antagonists; benzodiazepines; anesthetics; deep brain stimulation; transcranial magnetic stimulation; exogenous brain-derived neurotrophic factor; selective serotonin reuptake inhibitors; tricyclic antidepressants; atypical antidepressants; reduction in inflammation; and anti-inflammatory drugs.

It can take several months to recover from depression. Thus, Rao and Alderson write, current depression treatment programs that average six weeks “are not long enough for adequate recovery."