In the 1990s, drug manufacturers began marketing their products directly to consumers. Since then, prescription drug advertising has become a multibillion dollar industry, and some have worried that it might be getting between patients and what their doctors think is in their best interest.

But in a paper in the American Economic Journal: Microeconomics, author Bradley T. Shapiro found that advertising antidepressants on television led to significant improvements in indicators of depression. He says that the gains from decreasing workplace absenteeism far outweigh the costs associated with higher antidepressant sales.

Shapiro recently spoke with Tyler Smith about the challenges of estimating the impact of advertising on consumers and how direct-to-consumer advertising of antidepressants can improve mental health.