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

Depression is much more complicated than we thought, but new ideas about its biological causes have already led to promising treatments

CONTROVERSY has surrounded the most popular class of antidepressants ever since their development in the 1990s. Initially seen as wonder drugs, we have since come to realise that these selective serotonin reuptake inhibitors, or SSRIs, don’t help everyone and can cause unpleasant side effects.

The most recent cause for concern is that the once widely accepted explanation for how SSRIs work – namely by mitigating a lack of the brain chemical serotonin – is no longer thought to be correct. The unsettling conclusion is that, although the drugs work for many, we don’t know why.

It is clear that depression is …