A placebo is any substance that is passed off as medication, but in reality does not contain any medication at all. The result is that the person taking the placebo feels a perceived improvement in his condition. In some cases, the improvement is as real as if the person ingested medication. When this happens, the term placebo effect is used to describe the situation.
Placebos are commonly used in clinical trials in order to determine if the drug being tested is truly effective. What happens is that the researchers administer the real drug to one group and gives a placebo to another group. The results from each group are taken note of and compared.
The effective of a placebo is highly dependent on the person not knowing that he is being given a placebo. Therefore, in clinical trials, it is highly critical that the group being given the placebo are not informed of the fact. Otherwise, the results will probably be skewed.
The placebo effect can pose certain problems when a new drug is released in the market, especially if there is a lot of hype. Due to the hype, some people may experience the placebo effect and thus make the drug seem more effective than it really is.
Placebo pills can be made up of various ingredients, depending on the researchers conducting the clinical trials. One important consideration in making placebo pills is that the ingredients should not have any effect - positive or negative - on the condition being treated.