We have all heard of the ‘placebo effect’. WebMD.com describes a placebo as:
“anything that seems to be a “real” medical treatment – but isn’t. It could be a pill, a shot, or some other type of “fake” treatment. What all placebos have in common is that they do not contain an active substance meant to affect health.”
They go on to explain the placebo effect in the following way:
“Sometimes a person can have a response to a placebo. The response can be positive or negative. For instance, the person’s symptoms may improve. Or the person may have what appears to be side effects from the treatment. These responses are known as the “placebo effect.””
How does the placebo effect work?
A common explanation is that the placebo effect is a result of our expectations. If we expect a certain treatment to have a particular effect, perhaps our body chemistry in some way changes to cause that or a similar effect. Whatever its mechanism, it has been assumed that either deception or concealment of the true nature of the ‘treatment’ is necessary for a placebo to work.
A wrong assumption?
However, the results of four recent, small-scale studies suggests that assumption may not always be correct; that therapeutic benefit can still be gained even if a patient knows that a pill contains no medication – so called ‘open-label placebos’.
The studies, which have been published in the British Medical Journal, were co-ordinated by researchers at Harvard Medical School and Weill Cornell Medical College in the US.
Each of the four trials involved a different medical condition and over 60 people participated in each trial. One of those trials comprised 83 people suffering chronic low back pain. Participants were randomly divided into two groups, one taking a placebo plus their usual treatment and the other just their usual treatment. The study’s authors say that those taking the placebo were told that:
“it was not known whether open label placebo worked for their condition and testing this question was the purpose of the trial, with information provided transparently and neutrally. They were told about neurobiological and psychological evidence concerning placebo effects in general. The dialogue emphasised, “let’s see what happens.””
Despite knowing that the additional treatment they were taking was a placebo, the placebo group had a 28% reduction in pain after three weeks compared with just 9% in the usual treatment only group.
That sounds astonishing and seems to undermine entirely the assumption that deception or concealment are key to the placebo effect. While these results are statistically significant, the researchers have struggled to rationalise the mechanism behind them.
Once hypothesis is that although the participants knew they were taking a placebo and the placebo effect was explained to them, the way that it was explained could have led some to believe that they were receiving an active treatment, albeit not a pharmacological one.
Whatever the reason, with the long-term side-effects of taking medication often unknown, there is a very strong case here for a wider-scale study. If open-label placebos can help even a small proportion of people reduce their daily intake of medication, surely that has got to be worthwhile.