In 2004, the FDA warned the public that antidepressant use could increase the risk of suicidal thoughts or actions in adolescents--and it required all makers of antidepressant drugs to add to the drugs a dreaded "black box" warning. Now a group of researchers from Harvard is presenting rather compelling evidence that the FDA's action might have been a mistake.
In a study published in the British Medical Journal, the researchers report that attempted suicides by adolescents increased 21.7% two years after the FDA's warning, as antidepressant use fell by 31%. Attempted suicides among people between the ages of 18 and 29 soared 33.7%. The researchers came to those numbers by analyzing insurance claims data from 11 companies, using reports of drug poisonings to determine suicide attempts.
"After the widely publicized warnings we saw a substantial reduction in antidepressant use in all age groups," said the study's lead author, Christine Lu, an instructor at Harvard Pilgrim Health Care Institute, during an interview with Bloomberg. "Warnings, especially widely publicized warnings, may have unintended consequences."
The FDA's actions against antidepressants had ramifications well beyond America's borders. In 2008, the Medicines and Healthcare Regulatory Agency in the U.K. looked over the FDA's review of antidepressant safety data and concluded that the risk of suicide did indeed increase in young people who were taking the drugs. It proceeded to order a revising of the labels on a broad range of antidepressants, including Eli Lilly's ($LLY) Prozac, Pfizer's ($PFE) Effexor, and GlaxoSmithKline's ($GSK) Wellbutrin.
Some critics of the Harvard study say it's a stretch to tie the suicide attempts to the strongly worded warnings on the labels, however. "There's absolutely nothing in the study to say that these are the people who would have been prescribed the antidepressants if it weren't for the warnings," Marc Stone, a senior medical reviewer for the FDA, told Bloomberg.
Despite the controversy, antidepressants continue to rank among the most popular prescription products. A study released a few years ago by the CDC's National Center for Health Statistics revealed that 11% of Americans over age 12 were taking antidepressants between 2005 and 2008, making them the third most commonly prescribed drug in that age group.
And scientists continue to search for better ways to treat depression. Earlier this week, a team of researchers from UT Southwestern Medical Center revealed data showing that ketamine--the popular party drug known as "Special K"--may be a viable treatment option for depressed patients who don't respond to other medicines.