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Placebo effect underscored


The effectiveness of medication, such as a painkiller, can be heavily influenced by a patient’s expectation of its effect, a study has shown.

It seems “mind over matter” can work for some, albeit in a negative way.

Researchers carried out tests on 22 people to measure how manipulated thoughts can affect people’s perception of how effective a drug is.

Heat was applied to the participants’ legs, who were then asked to score the level of pain experienced on a scale of one to 100. Intravenous drips were also attached to each subject, secretly feeding them drugs.

Participants gave an average pain score of 66. They were then administered the drug remifantanil, a strong painkiller, and the average pain score dropped to 55. Participants were then told they were being given a painkiller and the average score dropped to 39.

After being told the painkiller was no longer being administered, although it actually still was, the average pain score increased to 64.

Oxford University professor Irene Tracey said: “It’s phenomenal. It’s really cool. It’s one of the best analgesics we have and the brain’s influence can either vastly increase its effect, or completely remove it.”

The study has been published in Science Translational Medicine.

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