For decades now the public has been told that depression is caused by a chemical imbalance and that antidepressants work by targeting this mechanism. Millions of people have decided to take antidepressants based on this information.Chemically Imbalanced tells the story of a scientific myth and its consequences. It traces the history of the serotonin theory of depression from its development in the 1960s, through its inculcation into popular culture in the 1990s, to the recent revelations that it is not supported by evidence.The story illustrates the power of human interests to shape what passes as scientific knowledge, and provides people with essential information about depression and antidepressants they will not readily find elsewhere. Above all else, Chemically Imbalanced is an invitation to better understand and advocate for our mental health.