In the 1950s, the discovery of two new drugs sparked what would become a multi-billion dollar market for antidepressants. Neither drug was intended to treat depression at all— many doctors and scientists believed psychotherapy was the only approach to treatment. Neil R. Jeyasingam details the decades-long journey that followed and how it revolutionized our understanding of depression.
https://www.ted.com/talks/neil_r_jeyasingam_how_do_antidepressants_work