The black box warning is the strongest statement the Food and Drug Administration (FDA) can require a drug company to issue. It is reserved for cases of serious or life threatening side effects. So it was a big deal in 2004 when the FDA forced drug companies to add a such a warning about increased suicidal thoughts in teens to a wide variety of antidepressants. The move was in response to some highly publicized 2003 findings about Paxil, one popular antidepressant.
That warning caused a dramatic drop in anti-depressant use by teenagers—20 to 30 percent. The results, according to a new working paper from the National Bureau of Economic Research:
Teen suicides increased:
Youth suicides had been flat or declining among 10-19 year olds in the years preceding the warnings, but in 2004, 10-19 year old girls experienced a sharp increase in suicides, of over 30 percent.
Depressed teens, primarily girls, experienced a drop in their grades, opening up an achievement gap between depressed and non-depressed teens that didn't exist before the warnings:
We find that in 2002 and 2003 adolescents with probable depression had grade point averages .14 to .20 points higher than adolescents with depression in the latter half of 2004 and 2005.
Use of illegal drugs by depressed teens increased:
In all cases but binge drinking, substance use was twice as common in the depressed adolescents compared with their non-depressed peers....
Among girls, the FDA advisories and decline in the treatment of depression increased the use of illicit drugs by 5.4 percentage points and increased nonmedical prescription drug use by 4.3 percentage points.
Depressed kids also got in more trouble:
Fighting and stealing both rose disproportionately among depressed adolescents in the post period. Fighting rose by 6.5 percentage points and stealing rose by 4.6 percentage points in the full sample, although the effects on stealing were driven entirely by depressed girls.
In other words, it looks like the FDA should consider a black box warning for its black box warning.
For more on depression, read this excellent 2007 piece by Will Wilkinson.