Why is the FDA scaring people about antidepressants?
The pediatrician Lawrence Diller, writing in The Washington Post, says the Food and Drug Administration has issued "an official warning…on the increased risks of suicidal tendencies when taking antidepressants such as Prozac." This is probably how most Americans interpreted the FDA's recent public health advisory covering 10 antidepressants.
Yet the FDA emphasizes it "has not concluded that these drugs cause worsening depression or suicide." Despite more than a decade of publicity about the alleged suicide-triggering properties of Prozac and its cousins, the FDA says, "a causal role for antidepressants in inducing such behaviors has not been established."
It is therefore hard to understand why the FDA is requiring that manufacturers of these drugs add a conspicuous suicide warning to their labels. The warning advises health care providers to "carefully monitor patients receiving antidepressants for possible worsening of depression or suicidality, especially at the beginning of therapy or when the dose either increases or decreases." It says "health providers should be aware that worsening of symptoms could be due to the underlying disease or might be the result of drug therapy."
The FDA defends the warning by arguing that it makes sense to keep an eye on depressed patients even if there's no truth to the claim that antidepressants make people kill themselves. "We think this is good advice whether the drugs did it or not," an FDA official told The New York Times. "If someone commits suicide, it doesn't really matter whether it's the drug or the underlying disease. In either case, you need to pay attention."
Putting aside the issue of whether people who feel happier after taking antidepressants are suffering from an "underlying disease," this rationale is rather strange. By the same logic, the FDA could require a warning that a heart drug might raise the risk of myocardial infarction not because there was good evidence that it did but because people with heart disease should be closely monitored.
Inevitably, the FDA's warning will lend credence to the lawsuit-inspiring claim the agency itself says has not been proven. Since people who take antidepressants tend to be depressed, it's hardly surprising that some of them think about, attempt, or commit suicide, thereby providing anecdotes for activists and trial lawyers. But we can never know how these people would have behaved without the antidepressants.
The FDA's decisions are not supposed to be based on anecdotes, which are emotionally compelling but scientifically unreliable. Instead the agency prides itself on demanding evidence from controlled, randomized, double-blind clinical trials. Such studies provide no evidence of an association between antidepressants and suicide in adults and only weak evidence of such a connection in children and teenagers.
The FDA is in the process of scrutinizing the data from the studies involving minors. None of the subjects actually committed suicide, and much of the uncertainty arises from the difficulty of classifying behavior as "possibly suicide-related" and deciding whether a particular action qualifies as a "suicide attempt."
The inconsistency of the findings creates further doubt. One study of Prozac, for instance, found that subjects taking the drug were more likely to attempt suicide than subjects given a placebo, while two others found just the opposite.
In any case, since the studies cited by the anti-antidepressant crowd involved minors diagnosed with "major depressive disorder," it's odd that the FDA's advisory covers all uses and all ages. Both the breadth of the advisory and its admittedly meager empirical basis suggest that preventing suicide is not the only motivation at work.
The New York Times reported that the advisory "grew at least partly from a concern that the drugs were being handed out too freely." It quoted a psychiatrist who predicted that as a result of the advisory doctors "will start limiting their use of [antidepressants] just to patients who are clearly depressed with clinically significant symptoms as opposed to those who have very mild symptoms."
This distinction does not really follow from a concern about suicide. Severely depressed patients are especially likely to kill themselves, meaning that not only the benefits but also the risks (if any) of taking antidepressants are higher for them. Conversely, mildly depressed people may enjoy less dramatic benefits, but any suicide risk also would be lower. It seems the controversy over antidepressants and suicide has become a cover for other, unarticulated concerns about the appropriate use of chemicals to tweak one's mood and personality.