So you’re taking your antidepressants faithfully and you’re more or less liking them, or at least you’ve gotten used to them, and to the side effects,  and to the idea that if you want to feel the way you’ve been feeling, you need to keep taking them. That’s a lot of adjusting you’ve had to do, and then one day you pick up the New York Times and it tells you that antidepressants only work better than placebos in severely depressed people. And you look it up in the DSM and discover that the book doesn’t really define “severe,”  but a close look at the actual diagnostic criteria makes it clear that severely depressed people, whatever they’re feeling,  are a whole lot worse off than you ever were. Which makes you wonder what in the world is going on, and to wish that they made a drug that counteracts antidepressant confusion.

And then you read about Irving Kirsch, the psychologist who started this whole business by prying loose the data used by drug companies to get FDA approval for their antidepressants and discovering that the drugs only beat the placebos about half the time, and then only by the narrowest of margins. Not only that, but Kirsch also says that most of the response even for the people who improve on the drug is the placebo effect. He reasons this way: drug takers in the successful clinical trials improve by around ten points on the Hamilton Depression Rating Scale, while placebo takers get about an eight-point boost, so we can presume that the first eight points are placebo, regardless of whether or not you are on the drug, which means that eighty percent of the improvement experienced by the drug takers is placebo effect.  That’s not as farfetched as it might sound. The whole idea of using placebos as stalking horses for drugs is based on subtraction: the drug effect is the improvement on drugs minus the improvement on placebos.

Kirsch also says that even that 20 percent is attributable to placebo–to what he calls the amplified placebo effect. What happens, he argues, is that people taking the real drug feel the side effects–the dry mouth or constipation or sexual troubles or jitteriness (or, if you’re lucky, all of them)–and conclude that they must be on the drug. That boosts their response even beyond what it would be just from the unamplified placebo effect, which, theoretically anyway, is the result of the healing relationship, the ritual of pill-taking, etc.

So does this mean you’ve been duped into thinking you’re doing better? Not hardly. I’ll explain in the next post.

This entry was posted on Sunday, March 28th, 2010 at 1:14 pm and is filed under Notes. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.