Depression is a serious problem, but drugs are not the answer. In the long run, psychotherapy is both cheaper and more effective, even for very serious levels of depression. Physical exercise and self-help books based on CBT can also be useful, either alone or in combination with therapy. Reducing social and economic inequality would also reduce the incidence of depression.
The Emperor's New Drugs: Exploding the Antidepressant Myth (ed. Basic Books, 2011) - ISBN: 9780465022007