We may be entering a bold new era in the treatment of depression

Depression is much more complex than we thought, but new ideas about its biological causes are already leading to promising treatments

Controversy surrounds the most popular class of antidepressants since they were developed in the 1990s. Initially viewed as a silver bullet, it was later realized that these selective serotonin reuptake inhibitors (SSRIs) do not work for everyone and can cause unpleasant side effects.

A recent source of concern is that the once widely accepted explanation for how SSRIs work—by alleviating deficiencies in the brain chemical serotonin—is no longer believed to be correct. The disturbing conclusion is that the drug works for many people, but we don’t know why.

Depression is obvious…