Antidepressant use among Americans is skyrocketing. Adults in the U.S. consumed four times more antidepressants in the late 2000s than they did in the early 1990s. As the third most frequently taken medication in the U.S., researchers estimate that 8 to 10 percent of the population is taking an antidepressant. But this spike does not necessarily signify a depression epidemic.

Through the early 2000s pharmaceutical companies were aggressively testing selective serotonin reuptake inhibitors (SSRIs), the dominant class of depression drug, for a variety of disorders—the timeline below shows the rapid expansion of FDA-approved uses.

As the drugs’ patents expired, companies stopped funding studies for official approval. Yet doctors have continued to prescribe them for more ailments. One motivating factor is that SSRIs are a fairly safe option for altering brain chemistry. Because we know so little about mental illness, many clinicians reason, we might as well try the pills already on the shelf.

– Julia Calderone

via The Rise of All-Purpose Antidepressants – Scientific American.