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I think the concept of placebos is such an interesting one. One thing I was wondering about was the interaction between (perhaps unknown) chemical reactivity of medications and the placebo effect. We mentioned in class that a large portion of the effects of many drugs may be because of a placebo effect. However, what happens when certain drugs (such as antidepressants) work for some people and not others. If someone is depressed and does not seem to have a favorable reaction to, say, Paxil, but then does to Zoloft, then how does the placebo effect fit in here? Is it possible that there is some effect of the way that the doctor introduced the medication or past research/news articles about the drug are impacting the way the person is reacting?

I located a study entitled by de Craen et al 2001 did a randomized double-blind study that gave an analgesic to study participants, with one group being told neutral information about the effects of the drug and the other being told that it is not usually a very effective pain killer. However they did not find any statistical difference between the pain management properties of the pill between the groups. (However there did seem to be increased effectiveness in both groups with the medication as compared to the placebo).

This study also mentions something that I've read before--that pill color, status of person administering drugs, and the route of administration all are factors that can influence therapeutic outcomes. People seem to react differently to medications based on the color and shape of the pills themselves. Often pills containing pseudoephedrine are red because "research has shown" that people find pills of that color to be better decongestants, and I believe this same type of research determined that viagra should be blue, but unfortunately I cannot remember where I read this. An article I found by de Craen et al (1996) does state that "available evidence suggests that green and blue may have more sedative effects and red and orange may have more stimulant effects." (I wonder what this means about viagra being blue...)

There just seem to be so many factors that play a role in how effective medication is to a person. I wonder which of these parts are officially the "placebo effect" and which function in some other capacity. It does make me wonder about the pills that I take quite a bit though, and how effective they may or may not be...